Faculty & Research - Physics
Graduate School of Science
Department of Condensed Matter Physics
Condensed matter physics is one of the most important research fields for the progress in science and technology in our society. Our staff members conduct cutting-edge research on quantum materials and provide physics education based on quantum mechanics and statistical mechanics. We aim to cross-fertilize research and education, and foster world-class human resources with creative talent. Students can expand their knowledge of modern quantum physics through the curriculum and can improve their logical thinking skills and capabilities for problem-finding and problem-solving through their research activities.
Condensed Matter Theory
Materials contain a huge number of electrons, typically in the order of Avogadro's number, which interact with each other via Coulomb forces and spin exchange. These interactions generate collective excitations, which in turn give rise to various properties such as superconductivity and magnetism at low temperatures. We are interested in such phenomena driven by many-body effects and are currently working on high-temperature superconductivity, interplay of superconductivity and magnetism, critical phenomena and quantum phase transition, and novel quantum states such as spontaneous symmetry breaking of the Fermi surface.
Our laboratory focuses on the study of nano-scale quantum/classical electrodynamics and energy transduction phenomena, emerging from the surface/interfaces of matters, especially from nano-scale objects. Chemical and physical fabrication as well as various lithographic techniques are adopted to realize novel nano materials/systems for effective energy transduction such as photothermal and photoelectric conversion. We aim at opening a new research field that can contribute for developing effective energy conversion materials based on light and heat harvesting nano-materials.
Solid State Physics in High Magnetic Fields
We have been studying electronic and spin properties in various materials such as quantum Hall systems, Graphene and topological insulators with high field magnets in NIMS. In particular, we use the spectroscopic technique in the wide range of the frequency between the millimeter-wave and the ultraviolet region for exploring anomalous and unusual features in solid.
Surface Quantum Phase Materials
The surface and the interface are places where the inside and the outside of a material are connected discontinuously, and because of this singularity, new quantum phases may occur there. In addition, they are easy to manipulate from the outside world and are known to often exhibit useful functions, which are important for device applications. The goals of our laboratory are to design and create two-dimensional quantum systems at surfaces and interfaces from atomic and molecular levels and to clarify their unknown material properties and functions. We will achieve them based on our own state-of-the-art UHV technique and nanotechnology. We are now leading the world in the field of atomic-layer superconductors on substrate surfaces.
Two-dimensional indium crystal on a silicon surface and its superconducting transition revealed by transport measurement
Schematic diagram of a Josephson superconducting vortex and its observation with a scanning tunneling microscope