Nemoto-Okuda Group

We know that a number of tiny elements can show most complex phenomena imaginable from their simplicity. Atoms and molecules can do this but also biological cells, small bees and human beings in their crowds may perform something incredible. We study such relation between microscopic elements and macroscopic phenomena in language of statistical physics.

Join us and make a scenario, for example, connecting a theory of phase transition with a behavior of crowd sardines fighting against a gigantic whale.

Keywords

• statistical physics
• non-equilibrium
• non-linearity
• random systems
• complex networks
• phase transition
• self-organization
• critical phenomena
• scale-free structures
• numerical simulation

Website

Kita Group

On the basis of many-body quantum field theory, we try to clarify phenomena characteristic of many-particle systems. For example, water composed of H2O molecules can exist in three different phases, i.e., water (liquid), ice (solid), and vapor (gas), which are remarkably different from each other. These phases are separated generally by phase transitions and broken symmetry, e.g., the one between water and ice. Many-particle systems obeying quantum mechanics exhibit a variety of distinct phases such as superconductivity without electrical resistance in some metals, Bose-Einstein condensation with superfluidity in atomic gases, and magnetism in metals and insulators. We are trying to elucidate these systems theoretically with a special focus on the interaction between particles.

Keywords

• Bose-Einstein condensation
• superfluidity
• quantum many-particle systems
• superconductivity
• spontaneous symmetry breaking
• Nambu-Goldstone boson
• Green’s function

Website

Hayami Group

We theoretically study novel physical phenomena in strongly-correlated electron systems based on quantum mechanics and statistical physics.
Our recent research subjects include

• Classification of electronic physical properties based on microscopic augmented multipoles
• Cross-correlated phenomena over electric, magnetic, elastic, heat, and light
• Stabilization mechanisms of novel electronic ordered states and superconductivity
• Topological spin states as a consequence of the interplay between topology and magnetism: skyrmion, hedgehog, and meron
• Search for function materials toward antiferromagnetic spintronics
• Efficient search for modeling and physical phenomena based on machine learning
• Quantitative analysis by ab-initio calculations of electronic band structure
• Analysis of unconventional electronic orderings and physical phenomena discovered in experiments

Hayami group page