Quantum decoherence due to nonlinear dynamics of environment

Hiroto Kubotani, Takashi Okamura, Masa‐aki Sakagami

Sun Chang-Pu

Sh. Dehdashti, M. Bagheri Harouni, Behrouz Mirza +1 more

In this paper, we study the role of the nonlinear environment on the bound passage time of dynamical quantum spin systems, which is of great interest in quantum control and has been applied to quantum metrology, quantum computation, and quantum chemical dynamics. We consider the decoherence speed limit for the spin-deformed bosonic model and the impacts of the nonlinear environment and its temperature on the decoherence speed limit. Moreover, we show that, at an early enough time, the parameters associated with the nonlinear environment exhibit important roles in controlling the decoherence process. In addition our results reveal that, in long times, these parameters do not affect the decoherence process.

Michael B. Mensky

G. P. Berman, A. R. Bishop, F. Borgonovi +1 more

When a quantum nonlinear system is linearly coupled to an infinite bath of harmonic oscillators, quantum coherence of the system is lost on a decoherence time scale ${\ensuremath{\tau}}_{D}$. Nevertheless, quantum effects for observables may still survive environment-induced decoherence and be observed for times much larger than the decoherence time scale. In particular, we show that the Ehrenfest time, which characterizes a departure of quantum dynamics for observables from the corresponding classical dynamics, can be observed for a quasiclassical nonlinear oscillator for times $\ensuremath{\tau}⪢{\ensuremath{\tau}}_{D}$. We discuss this observation in relation to recent experiments on quantum nonlinear systems in the quasiclassical region of parameters.