Publishing type：Research paper (international conference proceedings)   Publisher：Journal of the Physical Society of Japan  

DOI： 10.7566/jpscp.33.011125

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：International Union of Crystallography (IUCr)  

This paper presents an absolute X-ray photon energy measurement method that uses a Bond diffractometer. The proposed system enables the prompt and rapid <italic>in situ</italic> measurement of photon energies over a wide energy range. The diffractometer uses a reference silicon single-crystal plate and a highly accurate angle encoder called SelfA. The performance of the system is evaluated by repeatedly measuring the energy of the first excited state of the potassium-40 nuclide. The excitation energy is determined as 29829.39 (6) eV, and this is one order of magnitude more accurate than the previous measurement. The estimated uncertainty of the photon energy measurement was 0.7 p.p.m. as a standard deviation and the maximum observed deviation was 2 p.p.m.

DOI： 10.1107/s1600577520014526

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Atomic deexcitation emitting a neutrino pair and a photon is expected to provide a novel method of neutrino physics if it is enhanced by quantum coherence in a macroscopic target. However, the same enhancement mechanism may also lead to a serious problem of enhanced QED background process. We show that the QED background can be suppressed enough in the photonic crystal waveguide by using the spatial phase that is imprinted in the process of initial coherence generation in the target at excitation.

DOI： 10.1140/epjp/s13360-020-00290-2

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Other Link： http://link.springer.com/article/10.1140/epjp/s13360-020-00290-2/fulltext.html

Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP PUBLISHING LTD  

We study nearly degenerate four-wave mixing using a two-photon-allowed vibrational transition of parahydrogen. A signal photon is generated by a trigger photon and coherence among parahydrogen, which is prepared by two counterpropagating pump pulses, and we investigate the dependence of the signal pulse energy on the trigger frequency. The measured spectra depend on the geometry, shifting depending on the direction of the signal pulse and on the small angle formed by the counterpropagating pump pulses. Furthermore, we investigate the dependence of signal pulse energy on the incident time of the trigger pulse. The measured signal pulse energy is high if the trigger pulse is delayed slightly with respect to the pump pulses. We demonstrate that these geometry-dependent spectra and coherent-transient response can be explained by using simple models.

DOI： 10.1088/1361-6455/ab4a6e

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1038/s41586-019-1542-3

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP PUBLISHING LTD  

We observed two-photon emission (TPE) signal from the first vibrationally excited state of parahydrogen gas coherently excited by counter-propagating laser pulses. A single narrow-linewidth laser source has roles in the excitation of the parahydrogen molecules and the induction of the TPE process. We measured dependences of the signal energy on the detuning, target gas pressure, and input pulse energies. These results are qualitatively consistent with those obtained by numerical simulations based on Maxwell-Bloch equations with one spatial dimension and one temporal dimension. This study of the TPE process in the counterpropagating injection scheme is an important step toward neutrino mass spectroscopy.

DOI： 10.1088/1361-6455/aafbd0

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

This paper reports on the demonstration of a high-rate energy measurement technique using a thin depletion layer silicon avalanche photodiode (Si-APD). A dedicated amplitude-to-time converter is developed to realize simultaneous energy and timing measurement in a high rate condition. The energy response of the system is systematically studied by using monochromatic X-ray beam with an incident energy ranging from 6 to 33 keV. The obtained energy spectra contain clear peaks and tail distributions. The peak fraction monotonously decreases as the incident photon energy increases. This phenomenon can be explained by considering the distribution of the energy deposit in silicon, which is investigated by using a Monte Carlo simulation.

DOI： 10.1016/j.nima.2018.10.029

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society  

Nuclear resonant excitation and detection of its decay signal for the 26.27-keV level of Hg201 is demonstrated with high-brilliance synchrotron radiation (SR) and a fast x-ray detector system. This SR-based photonuclear excitation scheme, known as nuclear resonant scattering (NRS) in the field of materials science, is also useful for investigating nuclear properties, such as the half-lives and radiative widths of excited nuclear levels. To date, because of the limited time response of the x-ray detector, the nuclear levels to which this method could be applied have been limited to the one whose half-lives are longer than ∼1 ns. The faster time response of the NRS measurement makes possible NRS experiments on nuclear levels with much shorter half-lives. We have fabricated an x-ray detector system that has a time resolution of 56 ps and a shorter tail function than that reported previously. With the implemented detector system, the NRS signal of the 26.27-keV state of Hg201 could be clearly discriminated from the electronic scattering signal at an elapsed time of 1 ns after the SR pulse. The half-life of the state was determined as 629 ± 18 ps, which has better precision by a factor of three compared with that reported to date obtained from nuclear decay spectroscopy.

DOI： 10.1103/PhysRevC.97.024607

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP PUBLISHING LTD  

We report the coherent excitation of the vibrational state of hydrogen molecules by two-photon absorption and the resultant third-harmonic generation (THG). Parahydrogen molecules cooled by liquid nitrogen are irradiated by mid-infrared nanosecond pulses at 4.8 mu m with a nearly Fourier-transform-limited linewidth. The first excited vibrational state of parahydrogen is populated by two-photon absorption of the mid-infrared photons. Because of the narrow linewidth of the mid-infrared pulses, coherence between the ground and excited states is sufficient to induce higher-order processes. Near-infrared photons from the THG are observed at 1.6 mu m. The dependence of the intensity of the near-infrared radiation on mid-infrared pulse energy, target pressure, and cell length is determined. We used a simple formula for THG with consideration of realistic experimental conditions to explain the observed results.

DOI： 10.1088/1361-6455/aa9782

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER PHYSICAL SOC  

We investigate how the efficiency of coherently amplified two-photon emission depends on the frequency of one of the two emitted photons, namely the signal photon. This is done over the wavelength range of 5.048-10.21 mu m by using the vibrational transition of parahydrogen. The efficiency increases with the frequency of the signal photon. Considering experimental errors, our results are consistent with the theoretical prediction for the present experimental conditions. This study is an experimental demonstration of the frequency dependence of coherently amplified two-photon emission, and also presents its potential as a light source.

DOI： 10.1103/PhysRevA.96.063827

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER PHYSICAL SOC  

We study radiative neutrino pair emission in a deexcitation process of atoms taking into account the coherence effect in a macroscopic target system. In the course of preparing the coherent initial state to enhance the rate, a spatial phase factor is imprinted on the macroscopic target. It is shown that this initial spatial phase changes the kinematics of the radiative neutrino pair emission. We investigate effects of the initial spatial phase in the photon spectrum of the process. It turns out that the initial spatial phase provides us with significant improvements in exploring neutrino physics, such as the Dirac-Majorana distinction and the cosmic neutrino background.

DOI： 10.1103/PhysRevD.96.113005

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER INST PHYSICS  

We developed a fast X-ray detector system for nuclear resonant scattering (NRS) experiments. Our system employs silicon avalanche photo-diode (Si-APD) as a fast X-ray sensor. The system is able to acquire both timing and energy of a single X-ray photon simultaneously in a high rate condition, 106 counts per second for one Si-APD. The performance of the system was investigated in SPring-8, a synchrotron radiation facility in Japan. Good time resolution of 120 ps (FWHM) was achieved with a slight tail distribution in the time spectrum by a level of 10(-9) at 1 ns apart from the peak. Using this system, we successfully observed the NRS from the 26.27-keV level of mercury-201, which has a half-life of 630(50) ps. We also demonstrated the reduction of background events caused by radioactive decays in a radioactive sample by discriminating photon energy. Published by AIP Publishing.

DOI： 10.1063/1.4989405

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

We report the observation of two-photon emission from a coherently excited vibrational state of solid parahydrogen, which is also a known quantum solid. Coherence between the ground and the excited states is prepared by stimulated Raman scattering using two visible laser pulses. The two-photon emission is triggered by another mid-infrared laser pulse. It was observed that the two-photon emission persists even when the trigger pulse is injected long after the excitation. This is due to the long decoherence time of the vibrational states of solid parahydrogen. It is found that the emission intensity increases even after the excitation pulses pass through the target completely. This coherence development is highly suppressed at high target temperatures and high residual orthohydrogen concentrations. Effects of target annealing and laser-induced damage on the target are also observed.

DOI： 10.1021/acs.jpca.7b02011

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP PUBLISHING LTD  

We report on the generation of nanosecond mid-infrared pulses having frequency tunability, a narrow linewidth, and a high pulse energy. These pulses are obtained by frequency mixing between injection-seeded near-infrared pulses in potassium titanyl arsenate crystals. A continuous-wave external cavity laser diode or a Ti:sapphire ring laser is used as a tunable seeding source for the near-infrared pulses. The typical energy of the generated mid-infrared pulses is in the range of 0.4-1mJ/pulse. The tuning wavelength ranges from 3142 to 4806 nm. A narrow linewidth of 1.4GHz and good frequency reproducibility of the mid-infrared pulses are confirmed by observing a rovibrational absorption line of gaseous carbon monoxide at 4587 nm. (C) 2017 The Japan Society of Applied Physics

DOI： 10.7567/JJAP.56.032101

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PHYSICAL SOC JAPAN  

Previous experimental studies of superradiance (SR) in multi-level systems have been explainable using the predictions of the well-known simple two-level SR model. However our recent study [K. Nakajima et al., J. Phys. Soc. Jpn. 84, 054301 (2015)] using EUV free-electron laser excitation of helium atoms, where SR was observed at wavelengths of 502, 668, and 728 nm, revealed behaviour which necessitates a full multi-level treatment of the SR development. In this paper, we report simulations of the initial excitation by the FEL pulses, and the subsequent development of multi-level SR. The results of the simulation reproduce the experimental findings, and reveal that competitive SR on two transitions with a common upper level plays an important role in the development of the system.

DOI： 10.7566/JPSJ.85.034301

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IOP PUBLISHING LTD  

SPAN (SPectroscopy of Atomic Neutrino) project aims to determine the absolute neutrino mass. The process we plan to use is a cooperative de-excitation of atoms in a metastable level emitting a neutrino pair associated with a photon. The photon energy spectrum of this process contains information on the absolute mass of neutrino. Key items of this experiment are a rate amplification using macro-coherence in a target medium in case of plural particles emission and an external triggering of the emission in order to scan the spectrum. We have demonstrated the rate amplification in two-photon emission from para-hydrogen gas which was coherently excited to its first vibrationally excited state. The coherence in the medium was generated by irradiating two driving laser pulses. The emission was stimulated by irradiating a mid-infrared laser pulse. The enhancement factor of more than 10(18) with respect to the spontaneous emission was achieved. This paper briefly summarizes the results.

DOI： 10.1088/1742-6596/718/6/062043

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：SPRINGER  

We recently reported an experiment which focused on demonstrating the macro-coherent amplification mechanism. This mechanism, which was proposed for neutrino mass measurements, indicates that a multi-particle emission rate should be amplified by coherence in a suitable medium. Using a para-hydrogen molecule gas target and the adiabatic Raman excitation method, we observed that the two photon emission rate was amplified by a factor of more than 10(15) from the spontaneous emission rate. This paper briefly summarizes the previous experimental result and presents the current status and the future prospect.

DOI： 10.1007/s10751-015-1177-1

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS INC  

We report on coherent enhancement of two-photon emission from the excited vibrational state of molecular hydrogen triggered by irradiating mid-infrared pulses externally. We previously observed the two-photon emission triggered by the internally generated fourth Stokes photons. By injecting independent mid-infrared pulses externally, it is possible to control the experimental parameters and investigate the mechanism in more detail. In this article, we describe the two-photon emission using the external trigger pulses. Its spectrum and dependence on the energy and timing of the trigger pulse are presented along with numerical simulations based on the Maxwell-Bloch equations. The measured number of emitted photons is 6 x 10(11) photons/pulse and the resulting enhancement factor from the spontaneous emission is more than 10(18). This value is three orders of magnitude higher than that of the previous experiment. External control of the emission process is expected to be essential for observation of the weaker process of radiative emission of a neutrino pair.

DOI： 10.1093/ptep/ptv103

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS INC  

In this paper, we describe an experiment which was conducted to explore the macro-coherent amplification mechanism using a two-photon emission process from the first vibrationally excited state of the para-hydrogen molecule. Large coherence in the initial state was prepared by the adiabatic Raman method, and the lowest Stokes sideband was used as a trigger field. We observed coherent two-photon emission consistent with the expectation of the Maxwell-Bloch equation derived for the process, whose rate is larger by many orders of magnitude than that of spontaneous emission.

DOI： 10.1093/ptep/ptu152

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DOI： 10.1103/PhysRevD.90.013022

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER PHYSICAL SOC  

Metastable excited states P-3(2); P-3(0) of heavy alkaline earth atoms of even isotopes are studied for parity violating (PV) effects in radiative emission of neutrino pair (RENP). PV terms arise from interference between two diagrams containing neutrino pair emission of valence spin current and nuclear electroweak charge density proportional to the number of neutrons in nucleus. This mechanism gives large PV effects, since it does not suffer from the suppression of 1/(electron mass) usually present for nonrelativistic atomic electrons. A controllable magnetic field is crucial to identify RENP process by measuring PV observables. Results of PV asymmetries under the magnetic field reversal and the photon circular polarization reversal are presented for an example of Yb atom.

DOI： 10.1103/PhysRevD.90.013022

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PHYSICAL SOC JAPAN  

We describe in this paper a fast and efficient method of producing a high density of barium (Ba) atoms in the D-1(2) metastable state, which is a candidate initial state for a new class of cooperative and coherent optical process called paired superradiance (PSR). In the experiment, Ba atoms are excited first by laser light to the P-1(1) state and then brought to the desired state D-1(2) via radiative transition in the superradiance (SR) mode. It is found that a production efficiency (from S-1(0) to D-1(2)) of more than similar to 30% is achieved within a time interval of a few nanoseconds for a Ba density n > 10(19) m(-3). Several key features of SR important for future PSR experiments are also studied.

DOI： 10.7566/JPSJ.83.044301

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS INC  

It has recently been argued that atoms and molecules may become good targets for determining neutrino parameters still undetermined, if the atomic/molecular process is enhanced by a new kind of coherence. We compute the photon energy spectrum rate arising from coherent radiative neutrino pair emission processes of metastable excited states of I-2 and its isovalent molecules, vertical bar Av &gt; -&gt; vertical bar Xv'&gt; + gamma +nu(i)nu(j) and vertical bar A' v &gt; -&gt; vertical bar Xv '&gt; + gamma + nu(i)nu(j), with gamma an IR photon and nu(i(j)) the i (j)th neutrino mass eigenstates, and show how fundamental neutrino parameters may be determined. Energies of electronically excited states of I-2, including the effect of spin-orbit couplings, were calculated by the multiconfigurational second-order perturbation (CASPT2) method. Summation over many vibrational levels of intermediate states is fully incorporated. Unlike atomic candidates with a much larger energy difference, such as Xe, I-2 transitions from a vibrational level A(v = 0) to X(v' = 24) give us an opportunity to determine the mass type (Majorana vs Dirac distinction) and theMajorana CPV (charge-conjugation parity violating) phases, although the rate is much smaller.

DOI： 10.1093/ptep/ptt118

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Language：English   Publishing type：Research paper (scientific journal)  

Difference-frequency generation of 4.8 μm mid-infrared light was performed using a waveguide periodically poled LiNbO3 (PPLN) crystal. 871 and 1064 nm external-cavity diode lasers followed by tapered amplifiers were used as pump sources. A conversion efficiency of ̃2%/W with the output power of 2 mW was achieved even under considerable absorption of the crystal at this wavelength. Lamb-dip spectroscopy of carbonyl sulfide was demonstrated showing the satisfactory performance of this device for saturation spectroscopy. The observed dip width shows that the laser linewidth is ̃2 MHz, which corresponds to those of the pump lasers. © 2013 Optical Society of America.

DOI： 10.1364/OL.38.002825

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER PHYSICAL SOC  

We study a strongly interacting array of Bose-Einstein condensates trapped in a one-dimensional (1D) optical lattice. The system is described by a nonstandard 1D Bose-Hubbard model in which both the tunneling matrix element and the on-site atomic interaction depend on the lattice site due to the interaction broadening of the local wave function and the system inhomogeneity. We quantitatively compare theoretical analyses based on the Gutzwiller approximation with experimental observations obtained using ytterbium atoms. We show that atomic states are highly number squeezed owing to strong interatomic interactions as the lattice potential becomes deeper. Furthermore, the calculated inhomogeneous collisional broadening of spectroscopic line shapes agrees well with high-resolution spectra measured by using the ultranarrow magnetic quadrupole S-1(0)-P-3(2) transition.

DOI： 10.1103/PhysRevA.87.041604

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

Laser induced fluorescence (LIF) spectroscopy was applied to small bismuth clusters embedded in a solid neon matrix at 3 K. Near infrared (NIR) optical emission spectra were recorded in a range of 6200-11 600 cm(-1) by an excitation with 1.79 eV photons using a pulsed dye laser system. Three new NIR band systems were identified by their origin bands at 8207, 9625 and 11 395 cm(-1). Each of the NIR systems exhibited the vibrational progression with a common lower state frequency at 151 cm(-1). Temporal decay profiles for selected NIR emission bands showed upper state lifetimes on the order of a hundred of microseconds, explainable by the transition between mixed spin states. Low-lying electronic states for small bismuth clusters, Bi-n (n = 2-4), are discussed along the theory and experiment reported so far.

DOI： 10.1140/epjd/e2012-30529-x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER INST PHYSICS  

The coherence decay of the v = 2 vibrational state (vibrons) of solid parahydrogen was measured via time-resolved coherent anti-Stokes Raman spectroscopy. We found that the decay curve has a non-exponential time profile in the time scale of 200 ns at a low temperature below 5 K and a low orthohydrogen impurity concentration (similar to 0.01%). This behavior, as also observed in the case of the v = 1 vibrons, represents a signature of band structure of the v = 2 state in the solid phase. The maximum coherence decay time of 50 ns in an exponential part was achieved, which shows excellence of the v = 2 state for coherent processes. We also found that finite temperatures, orthohydrogen impurities, and other structural inhomogeneity accelerate the decay, hiding the non-exponential feature of the vibron band. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4773893]

DOI： 10.1063/1.4773893

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER PHYSICAL SOC  

Spin-polarized metastable atoms of ultracold ytterbium are trapped at high density and their inelastic collisional properties are measured. We reveal that in collisions of Yb(P-3(2)) with Yb(S-1(0)) there is relatively weak inelastic loss, but with a significant spin dependence consistent with Zeeman sublevel changes as being the dominant decay process. This is in strong contrast to our observations of Yb(P-3(2))-Yb(P-3(2)) collisional losses, which are, at low field, much more rapid and have essentially no spin dependence. Our results give a guideline to using the P-3(2) states in many possible applications.

DOI： 10.1103/PhysRevA.86.032712

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS INC  

We systematically investigate the new experimental method of using atoms or molecules to measure the important parameters of neutrinos that are still to be determined: the absolute mass scale, the mass hierarchy pattern (normal or inverted), the neutrino mass type (Majorana or Dirac), and the CP-violating phases, including Majorana phases. Most of these observables are difficult to measure in neutrino oscillation experiments. There are advantages to using atomic targets, such as the closeness of available atomic energies to anticipated neutrino masses, over nuclear target experiments such as the end point spectrum of beta decay and two-electron line spectrum in the neutrinoless double beta decay, both of which address some of the overlapping objectives with atomic/molecular experiments. A disadvantage of using atomic targets, the smallness of rates, is overcome by the macro-coherent amplification mechanism. The atomic or molecular process we use is a cooperative deexcitation of a collective body of atoms in a metastable level vertical bar e > emitting a neutrino pair and a photon: vertical bar e > -> vertical bar g > + gamma + nu(i)nu(j), where nu(i)s are neutrino mass eigenstates. The macro-coherence is developed by trigger-laser irradiation of two colors, which frequently causes the two-photon process vertical bar e > <-> vertical bar g > + gamma + gamma, vertical bar e > + gamma <-> vertical bar g > + gamma inside the target. We discuss important aspects of the macro-coherence development in detail, by setting up the master equation for the target Bloch vector (whose components are population difference and medium polarization) and the propagating electric field. Our master equation includes the effects of phase decoherence of medium polarization and decay of population difference. The spectral rate (the number of events per unit time) of macro-coherent radiative emission of a neutrino pair has three parts, and is given by a factorized formula of the form (overall omega-independent rate denoted by Gamma(0)) x (spectral shape function denoted by I (omega)) x (time-evolving dynamical factor), where omega is the photon energy. The constant factor Gamma(0) determines the overall rate in the unit of 1/time, and for Xe it is of the order of 1Hz(n/10(22) cm(-3))(3) (V/10(2) cm(3)). The dynamical factor is time dependent and is given by the space integrated quantity, over the entire target, of the product of the magnitude squared of the coherent polarization and the field strength (in the units of the maximally extractable energy density) stored inside the target. The asymptotic value of the time-evolving dynamical factor is given by the contribution of the field condensate accompanied by macroscopic coherence, which is calculated using the static limit of the master equation. With an appropriate choice of heavy target atoms or molecules such as Xe and I-2 that have a large M1 x E1 matrix element between vertical bar e > and vertical bar g >, we show that one can determine three neutrino masses along with distinction of the mass hierarchy pattern (normal or inverted) by measuring the spectral shape I (omega).If one uses a target of available energy of a fraction of 1 eV, the most experimentally challenging observable, the Majorana CP phases may be determined, comparing the detected rate with differences of theoretical expectations which exist at the level of several percent. The Majorana CP-violating phase is expected to be crucial to the understanding of the matter-antimatter imbalance in our universe. Our master equation, when applied to E1 x E1 transitions such as pH(2) vibrational Xv = 1 -> 0, can describe explosive paired superradiance events in which most of the energy stored in vertical bar e > is released in the order of a few nanoseconds. The present paper is intended to be self-contained, explaining some details of related theoretical works in the past, and reports on new simulations and the ongoing experimental efforts of the project to realize neutrino mass spectroscopy using atoms/molecules.

DOI： 10.1093/ptep/pts066

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Quantum degenerate gases of ytterbium atoms in three-dimensional optical lattices are studied for bosonic isotopes and mixtures of bosonic and fermionic isotopes. A quantum phase transition from a superfluid to a Mott insulating state is observed for bosonic isotopes. In the deep Mott insulating region, we perform one-color photoassociation spectroscopy and investigate the site occupancy. In addition, Bose-Fermi mixtures of Yb isotopes in optical lattices are studied using two different combinations of mixtures.

DOI： 10.3938/jkps.59.0

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：KOREAN PHYSICAL SOC  

Quantum degenerate gases of ytterbium atoms in three-dimensional optical lattices are studied for bosonic isotopes and mixtures of bosonic and fermionic isotopes. A quantum phase transition from a superfluid to a Mott insulating state is observed for bosonic isotopes. In the deep Mott insulating region, we perform one-color photoassociation spectroscopy and investigate the site occupancy. In addition, Bose-Fermi mixtures of Yb isotopes in optical lattices are studied using two different combinations of mixtures.

DOI： 10.3938/jkps.59.2936

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP PUBLISHING LTD  

High-resolution laser spectroscopy of a Bose-Einstein condensate (BEC) was performed by using the ultranarrow magnetic quadrupole (6s(2)) (1)S(0) &lt;-&gt; (6s6p) (3)P(2) transition of ytterbium (Yb). The transition from the Doppler-broadened spectrum of thermal atoms to the asymmetric spectrum, reflecting the inhomogeneous density distribution of a BEC in a harmonic trap, was observed. The role of the inter-atomic interaction was highlighted by performing spectroscopy of a BEC loaded in a one-dimensional (1D) optical lattice.

DOI： 10.1088/1367-2630/12/10/103001

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Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：The Laser Society of Japan  

Spectroscopy using an ultra-narrow linewidth transition is a sensitive tool to probe quantum degenerate

DOI： 10.2184/lsj.38.487

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Other Link： https://jlc.jst.go.jp/DN/JALC/00354404233?from=CiNii

Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

We have successfully implemented the first simultaneous magneto-optical trapping (MOT) of lithium ((6)Li) and ytterbium ((174)Yb) atoms towards production of ultracold polar molecules of LiYb. For this purpose, we developed the dual atomic oven which contains both atomic species as an atom source and successfully observed the spectra of the Li and Yb atoms in the atomic beams from the dual atomic oven. We constructed the vacuum chamber including the glass cell with the windows made of zinc selenium (ZnSe) for the CO(2) lasers, which are the useful light sources of optical trapping for evaporative and sympathetic cooling. Typical atom numbers and temperatures in the compressed MOT are 7x10(3) atoms, 640 mu K for (6)Li, 7x10(4) atoms, and 60 mu K for (174)Yb, respectively.

DOI： 10.1007/s00340-009-3728-0

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：WORLD SCIENTIFIC PUBL CO PTE LTD  

Quantum degenerate ytterbium(Yb) gases in 3D optical lattices are studied for bosonic isotopes and mixtures of bosonic and fermionic isotopes. In 3D optical lattices, a quantum phase transition from a superfluid to a Mott insulating state is observed. In the deep Mott insulating regime, one-color photoassociation(PA) spectroscopy is performed to probe site occupancy. Bose-Fermi mixtures of Yb isotopes in 3D optical lattices are also studied using two different combinations of mixtures.

DOI： 10.1142/9789814282345_0021

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

We propose a new quantum-computing scheme using ultracold neutral ytterbium atoms in an optical lattice, especially in a monolayer of three-dimensional optical lattice. The nuclear Zeeman sublevels define a qubit. This choice avoids the natural phase evolution due to the magnetic dipole interaction between qubits. The Zeeman sublevels with large magnetic moments in the long-lived metastable state are also exploited to address individual atoms and to construct a controlled-multiqubit gate. Estimated parameters required for this scheme show that this proposal is scalable and experimentally feasible.

DOI： 10.1007/s00340-009-3696-4

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We report results of frequency stability measurements of an extended cavity diode laser (ECDL) whose frequency is stabilized by a non-evacuated scanning transfer cavity. The transfer cavity is locked to a commercial frequency stabilized helium-neon laser. Frequency stability is measured by use of an optical frequency comb. The environmental perturbations (variations of temperature, air pressure, and humidity) are also simultaneously measured. The observed frequency drift of the ECDL is well explained by environmental perturbations. An atmospheric pressure variation, which is difficult to control with a non-evacuated cavity, is mainly affected to the frequency stability. Thus we put the cavity into a simple O-ring sealed (non-evacuated) tube. With this simple O-ring sealed tube, the frequency drift is reduced by a factor of 3, and the Allan variance reaches a value of 2.4x10(-10), corresponds to the frequency stability of 83 kHz, at the average time of 3000 s. Since the actual frequency drift is well estimated by simultaneous measurement of the ambient temperature, pressure, and humidity, a feed-forward compensation of frequency drifts is also feasible in order to achieve a higher frequency stability with a simple non-evacuated transfer cavity.

DOI： 10.1007/s00340-009-3619-4

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：WORLD SCIENTIFIC PUBL CO PTE LTD  

We have performed high-resolution spectroscopy of quantum degenerate gases of bosonic and fermionic ytterbium atoms using ultra-narrow intercombination transitions to probe quantum properties of the gases. The mean field interaction of the Bose-Einstein condensation and the energy distribution characteristic of the Fermi degeneracy were observed in the spectra.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER PHYSICAL SOC  

We report measurement of inelastic loss in dense and cold metastable ytterbium (Yb[(3)P(2)]). Use of an optical far-off-resonance trap enables us to trap atoms in all magnetic sublevels, removing m-changing collisional trap loss from the system. Trapped samples of Yb[(3)P(2)] are produced at a density of 2x10(13) cm(-3) and temperature of 2 mu K. We observe rapid two-body trap loss of Yb[(3)P(2)] and measure the inelastic collision rate constant 1.0(3)x10(-11) cm(3) s(-1). The existence of the fine-structure changing collisions between atoms in the (3)P(2) state is strongly suggested.

DOI： 10.1103/PhysRevLett.101.233002

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

DOI： 10.1007/s00340-008-3225-x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

We present a high-power and narrow-linewidth laser for intercombination magneto-optical trapping of ytterbium (Yb) atoms using the 6s(2) S-1(0)-6s6p P-3(1) transition. The system generates 415 mW of continuous wave laser radiation at 556 nm with a linewidth of less than 100 kHz. It is based on a commercial 1W fiber laser with a frequency doubling stage. Up to 58% frequency doubling efficiency is obtained at an input power of 0.5W by using a lithium triborate crystal as a nonlinear medium. The system has been successfully used for laser cooling of Yb atoms.

DOI： 10.1007/s00340-008-3062-y

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

A narrow-line diode laser system has been developed for high-resolution spectroscopy of the magnetic quadrupole transition in ytterbium (Yb) atoms at 507 nm. The system consists of an extended-cavity laser diode at 1014 nm, a tapered amplifier and a periodically poled lithium niobate nonlinear crystal which converts the wavelength from 1014 nm to 507 nm. We have stabilized the laser frequency and reduced the linewidth below 1 kHz by tightly locking the laser to a high-finesse optical cavity. By using the developed laser system, we have successfully observed the ultranarrow
S-1(0). &lt;-&gt;(3) P-2 transition in Yb atoms. Furthermore, our simple and compact laser system could be a high performance and portable frequency reference using iodine spectra whose linewidth becomes less than 50 kHz around 507 nm. We have also demonstrated spectroscopy of iodine molecules.

DOI： 10.1007/s00340-008-2953-2

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Language：English  

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IEEE  

We have all-optically created various quantum degenerate gases of ytterbium (Yb) atoms. The laser spectroscopy of ultra-narrow intercombination transitions S-1(0)-P-3(0) and S-1(0)-P-3(2) has been performed to probe the quantum degenerate gases of Yb atoms.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC APPLIED PHYSICS  

A simple and effective method for stabilizing laser frequencies using scanning transfer cavities and a stabilized helium-neon laser was applied to extended-cavity diode lasers near 866 nm and 397 run. The frequency drift of the stabilized 866 nm laser measured using an optical frequency synthesizer was smaller than 200 kHz for I h: The square root of the Allan variance was 1 x 10(-10) at an averaging time of 10(3) s.

DOI： 10.1143/JJAP.44.229

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Language：English   Publishing type：Research paper (international conference proceedings)  

We proceed with a research and development of an optical frequency standard based on the 2S1/2-2D5/2 transition of 43Ca+ in a RF trap. For this purpose, motional sidebands of a single 40Ca+ ion were observed and a stable laser-diode system for spectroscopy of 43Ca+ are being developed. ©2004 IEEE.

DOI： 10.1109/CPEM.2004.305293

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：INST PURE APPLIED PHYSICS  

We observed saturated absorption spectra of potassium at 404.8 nm with a frequency-stabilized violet diode laser. A diffraction grating in the Littrow configuration was used to get a single-mode output, and simultaneous resonant optical feedback from a confocal Fabry-Perot cavity was employed to stabilize the laser frequency. The observed short-term frequency fluctuations are 300 kHz for 1 s, and the upper limit on the instantaneous linewidth is 1.5 MHz. The optically locked laser can be continuously scanned over 4 GHz. The observed typical linewidth of the potassium transition is 3.6 MHz with a signal-to-noise ratio of 17. The transition is suitable for stabilizing frequency of violet diode lasers to a sub-MHz level.

DOI： 10.1143/JJAP.42.L332

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Institute of Electrical and Electronics Engineers Inc.  

A laser stabilization scheme is demonstrated, in which three external-cavity diode lasers (ECDLs) at 397 nm are simultaneously stabilized to a transfer cavity. The cavity is repeatedly scanned and the transmission peaks are compared to those of a 420 nm ECDL locked to a rubidium absorption line. This laser system is designed for laser cooling of a single 43Ca+ ion, which is assumed to be a promising candidate for quantum information processing as well as for optical frequency standards. Here the violet diode lasers have to stay within roughly one MHz during the actual experiments.

DOI： 10.1109/EQEC.2003.1314114

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OPTICAL SOC AMER  

We show that a liquid-hydrogen droplet can achieve high-Q values that exceed 10(9) for whispering-gallery modes in the ultraviolet. We show also that pumping high-Q liquid-hydrogen droplets with ultraviolet laser radiation generates many vibrational and rotational Raman sidebands that cover a broad spectral range from the ultraviolet to the near infrared. (C) 2002 Optical Society of America.

DOI： 10.1364/OL.27.000421

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：SPIE-INT SOC OPTICAL ENGINEERING  

Nonlinear optics in a liquid hydrogen droplet is discussed. We carry out the stimulated Raman scattering (SRS) experiments using high-Q whispering gallery modes. We show that the Liquid hydrogen droplet readily leads to high cavity Q-values exceeding 10(9) from ultraviolet to visible wavelength region. Using the high-Q liquid-hydrogen droplet, we demonstrate that, by pumping with an ultraviolet laser radiation, the SRS generates multiorder SRS sideband series through vibrational and rotational coherences covering whole ultraviolet-visible region from 200 nm to 900 nm, which may turn out as a super wideband optical comb generator. We also show that the SRS in the liquid hydrogen droplet proceeds for continuous operation with multiorder sidebands.

DOI： 10.1117/12.424665

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMERICAN PHYSICAL SOC  

Stimulated Raman scattering (SRS) is investigated in a liquid parahydrogen droplet. We show that the liquid hydrogen droplet readily leads to a high-cavity Q value exceeding 10(9) for whispering gallery modes, and that the SRS in the liquid-hydrogen droplet proceeds not only for vibrational transition but also for rotational transition as in the gas-phase H-2 system, leading to multiorder SRS sidebands covering the whole visible spectral range.

DOI： 10.1103/PhysRevA.61.011803

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Event date： 2023.9.16 - 2023.9.19

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2023.9.16 - 2023.9.19

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Event date： 2023.9.16 - 2023.9.19

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Event date： 2023.8.28

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Event date： 2023.6.2 - 2023.6.3

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Event date： 2023.3.22 - 2023.3.25

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Event date： 2023.3.22 - 2023.3.25

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Event date： 2023.3.22 - 2023.3.25

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Event date： 2023.3.22 - 2023.3.25

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Event date： 2022.9.12 - 2022.9.15

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Event date： 2022.9.6 - 2022.9.8

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Event date： 2022.9.6 - 2022.9.8

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Event date： 2022.8.29 - 2022.9.2

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Event date： 2022.7.17 - 2022.7.22

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Event date： 2022.7.17 - 2022.7.22

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Event date： 2022.7.17 - 2022.7.22

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Event date： 2022.3.15 - 2022.3.19

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Event date： 2022.3.15 - 2022.3.19

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Event date： 2022.3.15 - 2022.3.19

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Event date： 2022.3.15 - 2022.3.19

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Event date： 2022.3.15 - 2022.3.19

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Event date： 2022.3.15 - 2022.3.19

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Event date： 2022.1.6 - 2022.1.8

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Event date： 2021.9.20 - 2021.9.23

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2021.9.20 - 2021.9.23

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Event date： 2021.9.14 - 2021.9.17

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Event date： 2021.9.14 - 2021.9.17

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Event date： 2021.9.14 - 2021.9.17

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Event date： 2021.3.12 - 2021.3.15

Language：English   Presentation type：Oral presentation (general)  

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Event date： 2021.3.12 - 2021.3.15

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2021.3.12 - 2021.3.15

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Event date： 2021.3.12 - 2021.3.15

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Event date： 2021.3.12 - 2021.3.15

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2020.11.26 - 2020.11.28

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：大阪市立大学  

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Event date： 2020.9.15 - 2020.9.19

Language：English   Presentation type：Oral presentation (general)  

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Event date： 2020.9.15 - 2020.9.19

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2020.9.15 - 2020.9.18

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2020.6.1 - 2020.6.5

Language：English   Presentation type：Poster presentation  

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Event date： 2020.3.16 - 2020.3.19

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2020.3.16 - 2020.3.19

Language：English   Presentation type：Oral presentation (general)  

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Event date： 2020.3.16

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学（現地開催中止）  

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Event date： 2020.1.11

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：広島大学 (広島県)  

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Event date： 2019.11.27 - 2019.11.29

Language：English   Presentation type：Oral presentation (invited, special)  

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Event date： 2019.9.23 - 2019.9.27

Language：English   Presentation type：Oral presentation (invited, special)  

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Event date： 2019.9.17 - 2019.9.20

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：山形大学 (山形県)  

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Event date： 2019.9.17 - 2019.9.20

Language：English   Presentation type：Oral presentation (general)  

Venue：山形大学 (山形県)  

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Event date： 2019.9.17 - 2019.9.20

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2019.9.17 - 2019.9.20

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：山形大学 (山形県)  

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Event date： 2019.9.10 - 2019.9.13

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岐阜大学 (岐阜県)  

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Event date： 2019.9.10 - 2019.9.13

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岐阜大学 (岐阜県)  

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Event date： 2019.3.14 - 2019.3.17

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学 (福岡県)  

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Event date： 2019.3.14 - 2019.3.17

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学 (福岡県)  

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Event date： 2019.3.14 - 2019.3.17

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学 (福岡県)  

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Event date： 2019.3.14 - 2019.3.17

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学 (福岡県)  

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Event date： 2019.3.14 - 2019.3.17

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学 (福岡県)  

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Event date： 2019.3.1 - 2019.3.4

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：OIST (沖縄県)  

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Event date： 2019.3.1 - 2019.3.4

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：OIST (沖縄県)  

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Event date： 2019.3.1 - 2019.3.4

Language：English   Presentation type：Poster presentation  

Venue：OIST (沖縄県)  

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Event date： 2019.1.7 - 2019.1.8

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：大阪大学 (大阪府)  

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Event date： 2018.12.10 - 2018.12.11

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：大阪大学 (大阪府)  

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Event date： 2018.11.27 - 2018.11.29

Language：English   Presentation type：Poster presentation  

Venue：東京大学 (東京都)  

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Event date： 2018.10.23 - 2018.10.27

Language：English   Presentation type：Oral presentation (general)  

Venue：Hawaii (USA)  

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Event date： 2018.9.21

Language：Japanese  

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Event date： 2018.9.14 - 2018.9.17

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：信州大学(長野県)  

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Event date： 2018.9.14 - 2018.9.17

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：信州大学(長野県)  

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Event date： 2018.9.9 - 2018.9.12

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：同志社大学(京都府)  

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Event date： 2018.7.22 - 2018.7.27

Language：English   Presentation type：Poster presentation  

Venue：Barcelona, Spain  

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Event date： 2018.7.22 - 2018.7.27

Language：English   Presentation type：Poster presentation  

Venue：Barcelona, Spain  

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Event date： 2018.7.22 - 2018.7.27

Language：English   Presentation type：Poster presentation  

Venue：Barcelona, Spain  

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Event date： 2018.3.22 - 2018.3.25

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京理科大学(千葉県)  

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Event date： 2018.3.22 - 2018.3.25

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京理科大学(千葉県)  

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Event date： 2018.3.22 - 2018.3.25

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京理科大学(千葉県)  

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Event date： 2018.1.23

Language：Japanese   Presentation type：Poster presentation  

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Event date： 2018.1.8 - 2018.1.9

Language：English   Presentation type：Oral presentation (invited, special)  

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Event date： 2018.1.8 - 2018.1.9

Language：English   Presentation type：Poster presentation  

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Event date： 2018.1.8 - 2018.1.9

Language：English   Presentation type：Poster presentation  

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Event date： 2018.1.8 - 2018.1.9

Language：English   Presentation type：Poster presentation  

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Event date： 2018.1.8 - 2018.1.9

Language：English   Presentation type：Poster presentation  

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Event date： 2018.1.8 - 2018.1.9

Language：English   Presentation type：Poster presentation  

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Event date： 2018.1.8 - 2018.1.9

Language：English   Presentation type：Poster presentation  

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Event date： 2018.1.8 - 2018.1.9

Language：English   Presentation type：Oral presentation (invited, special)  

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Event date： 2018

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2017.10.21 - 2017.10.28

Language：English   Presentation type：Oral presentation (general)  

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Event date： 2017.9.21 - 2017.9.24

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岩手大学(岩手県)  

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Event date： 2017.9.12 - 2017.9.15

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：宇都宮大学(栃木県)  

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Event date： 2017.9.12 - 2017.9.15

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：宇都宮大学(栃木県)  

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Event date： 2017.7.2 - 2017.7.8

Language：English   Presentation type：Poster presentation  

Venue：Palais des Congres, Arcachon, France  

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Event date： 2017.7.2 - 2017.7.8

Language：English   Presentation type：Poster presentation  

Venue：Palais des Congres, Arcachon, France  

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Event date： 2017.4.19 - 2017.4.21

Language：English   Presentation type：Oral presentation (invited, special)  

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Event date： 2017.3.21

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2017.3.17 - 2017.3.20

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：大阪大学(大阪府)  

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Event date： 2017.3.17 - 2017.3.20

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：大阪大学(大阪府)  

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Event date： 2017.1.9 - 2017.1.10

Language：English   Presentation type：Poster presentation  

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Event date： 2017.1.9 - 2017.1.10

Language：English   Presentation type：Oral presentation (invited, special)  

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Event date： 2017.1.9 - 2017.1.10

Language：English   Presentation type：Poster presentation  

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Event date： 2017.1.9 - 2017.1.10

Language：English   Presentation type：Oral presentation (invited, special)  

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Event date： 2017.1.9 - 2017.1.10

Language：English   Presentation type：Poster presentation  

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Event date： 2017

Language：Japanese  

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Event date： 2016.9.23

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2016.9.21 - 2016.9.24

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：宮崎大学(宮崎県)  

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Event date： 2016.7.24 - 2016.7.29

Language：English   Presentation type：Poster presentation  

Venue：Auditorium, COEX, Seoul, Korea  

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Event date： 2016.7.24 - 2016.7.29

Language：English   Presentation type：Poster presentation  

Venue：Auditorium, COEX, Seoul, Korea  

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Event date： 2016.3.19 - 2016.3.22

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東北学院大学(宮城県)  

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Event date： 2016.3.19 - 2016.3.22

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東北学院大学(宮城県)  

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Event date： 2016

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2016

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2015.9.25 - 2015.9.28

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：大阪市立大学(大阪府)  

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Event date： 2015.9.25 - 2015.9.28

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：大阪市立大学(大阪府)  

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Event date： 2015.3.21 - 2015.3.24

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：早稲田大学(東京都)  

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Event date： 2015.3.21 - 2015.3.24

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：早稲田大学(東京都)  

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Event date： 2015.3.21 - 2015.3.24

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：早稲田大学(東京都)  

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Event date： 2015.3.21 - 2015.3.24

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：早稲田大学(東京都)  

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Event date： 2015.1.11 - 2015.1.12

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東海大学(東京都)  

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Event date： 2015

Language：Japanese  

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Event date： 2015

Language：Japanese  

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Event date： 2014.11.28 - 2014.12.5

Language：English   Presentation type：Poster presentation  

Venue：Kagawa International Conference Hall, Kagawa, Japan  

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Event date： 2014.9.18 - 2014.9.21

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：佐賀大学(佐賀県)  

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Event date： 2014.9.18 - 2014.9.21

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：佐賀大学(佐賀県)  

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Event date： 2014.9.18 - 2014.9.21

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：佐賀大学(佐賀県)  

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Event date： 2014.9.18 - 2014.9.21

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：佐賀大学(佐賀県)  

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Event date： 2014.9.17 - 2014.9.20

Language：English   Presentation type：Oral presentation (general)  

Venue：北海道大学(北海道)  

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Event date： 2014.9.7 - 2014.9.10

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：中部大学(愛知県)  

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Event date： 2014.9.7 - 2014.9.10

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：中部大学(愛知県)  

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Event date： 2014.8.22

Language：Japanese  

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Event date： 2014.8.22

Language：Japanese  

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Event date： 2014.8.22

Language：Japanese  

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Event date： 2014.8.3 - 2014.8.8

Language：English   Presentation type：Poster presentation  

Venue：Mayflower Renaissance Hotel, Washington, D.C. USA  

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Event date： 2014.8.3 - 2014.8.8

Language：English   Presentation type：Poster presentation  

Venue：Mayflower Renaissance Hotel, Washington, D.C. USA  

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Event date： 2014.8.3 - 2014.8.8

Language：English   Presentation type：Poster presentation  

Venue：Mayflower Renaissance Hotel, Washington, D.C. USA  

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Event date： 2014.3.27 - 2014.3.30

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東海大学(神奈川県)  

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Event date： 2014.3.27 - 2014.3.30

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東海大学(神奈川県)  

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Event date： 2014.3.14 - 2014.3.16

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：日本科学未来館(東京都)  

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Event date： 2014.1.20 - 2014.1.22

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：北九州国際会議場(福岡県)  

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Event date： 2013.9.20 - 2013.9.23

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：高知大学(高知県)  

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Event date： 2013.3.27 - 2013.3.30

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：神奈川工科大学(神奈川県)  

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Event date： 2013.3.26 - 2013.3.29

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：広島大学(広島県)  

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Event date： 2013.3.26 - 2013.3.29

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：広島大学(広島県)  

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Event date： 2013

Language：Japanese  

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Event date： 2013

Language：Japanese  

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Event date： 2012.9.11 - 2012.9.14

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都産業大学(京都府)  

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Event date： 2012.9.11 - 2012.9.14

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：愛媛大学(愛媛県)  

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Event date： 2012.7.8 - 2012.7.13

Language：English   Presentation type：Poster presentation  

Venue：Leuven, Belgium  

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Event date： 2012.3.24 - 2012.3.27

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：関西学院大学(兵庫県)  

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Event date： 2012.3.24 - 2012.3.27

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：関西学院大学(兵庫県)  

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Event date： 2012.3.24 - 2012.3.27

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：関西学院大学(兵庫県)  

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Event date： 2012.3.24 - 2012.3.27

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：関西学院大学(兵庫県)  

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Event date： 2012.3.5

Language：Japanese  

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Event date： 2012

Language：Japanese  

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Event date： 2012

Language：Japanese  

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Event date： 2012

Language：Japanese  

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Event date： 2011.6.26 - 2011.7.1

Language：English   Presentation type：Poster presentation  

Venue：Vermont, USA  

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Event date： 2010.9.23 - 2010.9.26

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：大阪府立大学(大阪府)  

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Event date： 2010.9.22 - 2010.9.26

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Toyama, Japan  

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Event date： 2010.4.9

Language：Japanese   Presentation type：Poster presentation  

Venue：日本学術会議講堂(東京)  

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Event date： 2010.4.6 - 2010.4.9

Language：English   Presentation type：Poster presentation  

Venue：Tokyo, Japan  

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Event date： 2010.3.20 - 2010.3.23

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岡山大学 (岡山県)  

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Event date： 2009.9.25 - 2009.9.28

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：熊本大学(熊本)  

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Event date： 2009.9.25 - 2009.9.28

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：熊本大学(熊本)  

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Event date： 2009.9.25 - 2009.9.28

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：熊本大学(熊本)  

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Event date： 2009.8.18

Language：Japanese  

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Event date： 2009.6.23 - 2009.6.26

Language：English   Presentation type：Poster presentation  

Venue：Kyoto, Japan  

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Event date： 2009.6.23 - 2009.6.26

Language：English   Presentation type：Poster presentation  

Venue：Kyoto, Japan  

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Event date： 2009.6.23 - 2009.6.26

Language：English   Presentation type：Poster presentation  

Venue：Kyoto, Japan  

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Event date： 2009.6.7 - 2009.6.13

Language：English   Presentation type：Poster presentation  

Venue：Hokkaido, Japan  

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Event date： 2009.6.7 - 2009.6.13

Language：English   Presentation type：Poster presentation  

Venue：Hokkaido, Japan  

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Event date： 2009.3.27 - 2009.3.30

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：立教大学(東京)  

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Event date： 2009.3.27 - 2009.3.30

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：立教大学(東京)  

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Event date： 2002.8.13

Language：Japanese  

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