2025/01/28 by Shohei Imai, Atsushi Ono, Imai, Shohei +3 · 3 citations
Physics and Astronomy · #Quantum optics and atomic interactions #Laser-Matter Interactions and Applications #Spectroscopy and Quantum Chemical Studies
paper · pdf · doi:10.1103/7vll-vh3l
We present an effective theory for describing electron dynamics driven by an optical external field in a Schrödinger's cat state. We show that the reduced electron density matrix evolves as an average over trajectories \ρα\ weighted by the Sudarshan--Glauber P distribution P(α) in the weak light--matter coupling regime. Each trajectory obeys an equation of motion, i ∂tρα=Hα ρα-ραHα, where an effective Hamiltonian Hα becomes non-Hermitian due to quantum interference of light. The optical quantum interference is transferred to electrons through the asymmetric action between the ket and bra state vectors in ρα. This non-Hermitian dynamics differs from the conventional one observed in open quantum systems, described by i ∂tρ=Hρ-ρH^†, which has complex conjugation in the second term. We confirm that the reduced, trajectory-resolved effective theory agrees with full electron-photon simulations for the few-electron Dicke model, thereby validating the interferential non-Hermitian description in the weak-coupling regime.