Speaker
Description
In this talk, I present an interesting connection between quantum dynamics in an isolated system and that in an open system. Although the dynamics is unitary in isolated systems, we often observe exponential decays of physical quantities in a certain time window. In classical chaos, such exponential decays are characterized by poles of the resolvent of the time evolution operator (or the Hamiltonian) in complex plane, which are known as Ruelle-Pollicott resonances. I will tell you that there is a quantum analogue of the concept of Ruelle-Pollicott resonances in quantum spin systems which are far from the classical limit, and that quantum Ruelle-Pollicott resonances are extracted by investigating noisy quantum dynamics that is obtained by introducing weak noise to the pure unitary dynamics.