One of the greatest challenges in contemporary physics is to understand the various complex systems in nature. Nonlinear interaction between each element is a major cause of the system's complexity, and therefore the theory of nonlinear dynamics plays an important role in the approach to such issues. The main interests in our laboratory are chaotic dynamics in classical Hamiltonian systems and quantum manifestations of classical chaos (quantum chaos). In particular, we are focusing on quantum tunneling in the presence of chaos; complex WKB methods in chaotic systems; slow relaxation in Hamiltonian systems with internal degrees of freedom; chaotic open quantum systems; and formalisms on adiabatic phenomena.
