Assoc. Prof. Hiroshi Kohguchi, Hiroshima University, Japan
Biography: Dr. Kohguchi graduated from the University of Tokyo, and received M. Sc and Ph. D in Pure and Applied Sciences from the University of Tokyo, Japan. He started his academic carrier as a research associate in Institute for Molecular Science (IMS) in 1996, and moved to the chemical dynamics laboratory in RIKEN as a scientific researcher in 2002. From 2008, he has his position as an associate professor in the department of chemistry at Hiroshima University. In the period of 2016 – 2018, he stayed in Cologne University in Germany as a visiting researcher. His research area is chemical reaction dynamics and molecular spectroscopy. His recent interest is recently expanding to photochemical control of transition-metal complexes, peptides, and amines.
Speech Title: Dynamical Alignment of Photoeliminated Ligands from Transition Metal Complexes
Abstract—Transition-metal (TM) complexes are characterized by highly symmetric structures, dense electronic structures, and low bond dissociation energies (100-200 kJ/mol) compared to organic compounds. Photoexcitation of TM complexes into the dense electronic states arising from the d-orbitals shows ultrafast relaxation (> 10 fs), and sequential loss of a variety of ligands, which are poorly understood. Photoinduced elimination of heteroleptic TM complexes provide understandings of the reactivity and bond-selectivity for photocatalysis. We have investigated photodissociation of Co(CO)3NO from the viewpoint of nascent distributions of liberated ligands.
Asst. Prof. Leo Matsuoka, Hiroshima University, Japan
Biography: Dr. Matsuoka graduated from the University of Tokyo, and received M. Sc and Ph. D in Engineering from the University of Tokyo, Japan. He started his academic carrier as a postdoctoral fellow in Japan Atomic Energy Agency (JAEA) in 2007. From 2013, he has his position as an assistant professor in the graduate school of Engineering at Hiroshima University. His research area is atomic, molecular and optical physics by experimental, numerical, or mathematical approaches. His recent interest is laser isotope separation of atomic cesium with high efficiency in the thermal equilibrium.
Speech Title: Development of a Highly Efficient Laser-based Method of Radioactive Cs Isotope Separation Utilizing Light-induced Drift
Abstract—The separation of cesium isotopes is required for effective nuclear transmutation aiming for reducing radioactive wastes. We propose the isotope separation by light-induced drift for cesium isotopes. This method is highly efficient because the isotopes are separated continuously in time in the thermal equilibrium. First, we show a numerical estimation of the efficiency of the separation by using newly calculated interatomic potentials. Second, we show our experimental system to implement the light-induced drift of the cesium atoms including some low-cost original modules. Finally, we show the result of the light-induced drift in our experimental system.
Asst. Prof. Shin-ichi Wada, Hiroshima University, Japan
Biography: Dr. Wada graduated from Tokyo Institute of Technology, and received M. Sc and Ph. D in the field of laser spectroscopy from Tokyo Institute of Technology, Japan. He was a postdoctoral fellow of National Institute for Advanced Interdisciplinary Research in Japan, and then moved to the soft X-ray photochemistry laboratory in Department of Physical Science, Hiroshima University as a research associate (1998). From 2006, his position has been assistant professor (2007-). In the period of 2010-2011, he stayed in SLAC National Accelerator Laboratory in USA as a visiting researcher, and was a visiting researcher in SPring-8 Center in RIKEN (2010-2017). His research area is chemical reaction dynamics and photochemistry of organic surfaces and nanomaterials by using synchrotron radiation (SR), ultrafast optical laser, and X-ray free electron laser (XFEL).
Speech Title: Evaluation of Molecular Conductivity of Organic Monolayers Utilizing Core-electron Excitations
Abstract—Core-electron excitations take place within a small region because of their spatial localization and atomic selectivity. Therefore, soft x-ray irradiation can excite a specific atom in a molecule selectively and often bring site-selective ionic bond breaking. It is generally understood that such bond breaking is promoted by the Coulomb repulsion between two holes at local bonding orbitals and the suppression of bonding power due to one electron at an anti-bonding orbital (so-called spectator Auger final states). This reaction can be obviously observed on solid surfaces as ion desorption, particularly well-ordered monolayers, indicating the importance of the interaction between functional group at outermost surface (reaction center) and substrate. In this study, we investigated correlation between charge transfer (CT) and reaction dynamics of organic monolayers (SAMs) induced by resonant core excitations. For conductive aromatic SAMs, ultrafast CT which can compete core-hole lifetime was evaluated by Auger decay dynamics. On the other hand, for insulating aliphatic SAMs, fragmentation ratio of selectively desorbing ions was evaluated by estimating statistical redistribution of excess energy after CT. These findings suggest that core-excitation dynamics measurement is a useful candidate to conveniently evaluate molecular conductivity with a wide range.
Asst. Prof. Masataka Iinuma, Hiroshima University, Japan
Biography: Dr. Iinuma graduated from Chiba University and obtained M.Sc and Ph.D in Physics from Kyoto University, Japan. He was a research associate in Faculty of Science, Hiroshima University (1997) and moved to Graduate school of Advanced Sciences of Matter (ADSM), which is one of divisions in Hiroshima University (1998-2006). During the period, he stayed at University of Washington, USA, as a visiting researcher for one year in 2000. From 2006, his position has been Assistant Professor (2007-). His research area is experimental investigation on particle and nuclear physics, quantum foundation, quantum optics, and quantum electronics. Particularly, his recent interest is experiments on quantum foundation in photonic systems by using quantum information technology.
Speech Title: Nonclassical Correlation between Two Noncommuting Polarizations in Sequential Quantum Measurements
Abstract—A sequence of two quantum measurements for a pair of noncommuting observables, which is composed of a variable strength measurement followed by a fully projective measurement, allows us to observe an experimental correlation between them and measure a joint probability distribution with finite measurement and backaction errors, which includes the quasiprobability distribution in the initial state. In quantum theory, since many types of quasiprobabilities are defined, such as the Wigner function, the P function, etc., it is generally considered that they are merely one of mathematical expressions. On the other hands, the commutation relation between two noncommuting observables naturally leads to the imaginary correlation, which implies that the joint quasiprobabilites should take complex numbers. However, it is not easy to observe the imaginary correlation, because the direct observation is impossible due to the uncertainty principle. For experimentally investigating it, as the first step, we have limited the two-level systems and preformed two experiments using photon polarizations. One experiment is intended to observe the experimental correlation from the sequential quantum measurements for obtaining the imaginary correlation and the other is to evaluate the error of the imaginary correlation in the joint measurement. Through two experiments, we have been able to show that the intrinsic imaginary correlation is converted into the real number in the measurement process due to the measurement uncertainty. It is concluded that the contradiction to the normal classical statistics is unavoidable.
Prof. Rakesh Chand Ramola, HNB Garhwal University, India
Speech Title: Analysis of Ion Beam Irradiated ZnO:Ga Thin Film for Gas Sensing
Abstract—Zinc oxide (ZnO) is one of the most prominent metal oxide semiconductors with wide band energy gap of 3.37 eV and large exciting binding energy of 60 MeV. Due to its good electrical and optical properties, thermal and chemical stability, abundance in nature, low cost and absence of toxicity, it have wide applications in electronic and optoelectronic devices such as transparent conductors, solar cell window, surface acoustic wave (SAW) devices, heat mirrors and gas sensing applications. For gas sensing application, ZnO in thin film form is more suitable because the gas sensing properties are related to the material surface, where the gases are adsorbed and the surface reactions occur.
Swift heavy ion irradiation is used as unique tool to modify the structural, electrical and optical properties of materials, which improves the efficiency of device to great extent. In present investigation, the response and recovery time, sensitivity and selectivity of Ga doped ZnO thin film modified by ion beam irradiation are analysed. The gas sensing properties of ion beam irradiated gallium doped ZnO thin films were also studied. The Ag9+ and Si6+ irradiated gallium doped zinc oxide thin films were exposed with different concentrations of ethanol and acetone gas for gas sensing applications. The Ag9+ ion irradiated ZnO:Ga doped thin film was optimized at 500 °C temperature. It was observed that gas sensing response for both ethanol and acetone gas vapours increases with increasing Ag9+ ion fluence. This means the swift heavy ion have improved the sensitivity of ZnO:Ga by the reducing the particle size. The Si6+ ion irradiated ZnO:Ga thin films were also exposed with ethanol and acetone gas for gas sensing application. The film irradiated with Si6+ ion beam show higher sensing response for both ethanol and acetone gas in comparison of Ag9+ ion irradiated thin film.