Non-Hermitian Physics and Open Quantum Systems

Non-Hermitian physics provides effective descriptions of systems with gain, loss, and environmental coupling. We investigate parity-time-symmetric quantum optical models, exceptional-point structures, and dynamical signatures that go beyond semiclassical treatments.

A complementary focus is open quantum systems, including the effects of two-photon relaxation on quantum Rabi models. We study how environmental coupling and dissipation reshape quantum dynamics and steady states. Effective non-Hermitian descriptions and full open-system evolution are related but distinct tools; their connection depends on the physical setting and the treatment of quantum jumps.

Ongoing research examines dissipative phase transitions, Liouvillian exceptional points, and quantum Mpemba effects. These topics extend our published work on the PT-symmetric quantum Rabi model (2023) and two-photon relaxation (2024).