Wei Jaing
Beijing Normal University, China
Title: Non-Markovian entanglement dynamics of continuous measurement feedback open quantum system in structured bath
Biography
Biography: Wei Jaing
Abstract
In the past two decades, entanglement has attracted much attention continuously for its potential use as the key resource of quantum computation and quantum information. Due to decoherence of a system coupling to its environment or bath, entanglement degradation is unavoidable. In this work we investigate the entanglement dynamics of two two-state quantum systems coupling to a Bosonic mode and a common structured bath. Here the Bosonic mode, which is resonantly driven by a classical filed and heavily damped by a broadband reservoir, acts as a probe resonator for the use of continuous quantum measurement feedback, and the bath has one of three different structures characterized by the Ohmic types of spectral densities. We proceed by using hierarchical equations of motion (HEOM) approach. We present the master equation of the reduced density matrix for the system investigated and, accordingly, the HEOM for auxiliary operators. The HEOM calculation shows that the quantum measurement feedback plays a positive role in the entanglement generation, and the non-Markovian effect of the bath could greatly enhances this action, increasing the entanglement by 50% in the case of, for example, the Ohmic bath. We reveal in detail the dependence of the scheme performance on the spectral density parameters, the temperature of the bath, and the measurement feedback. The numerical results are obtained with the HEOM truncated at the 3rd order, which are equal to those obtained with the 6th order perturbation theory.