Modeling and Analysis of Non-Markovian Open Quantum Systems for Coherent Feedback

This paper presents a model for coherent feedback control of non-Markovian open quantum systems, where an integral-differential Langevin equation is derived to describe the controlled dynamics of the non-Markovian system. Moreover, a Green function based root locus method is presented to analyze the non-Markovian dynamics of the system under coherent feedback control in the frequency domain. Utilizing the quantum tunneling effect, our coherent feedback scheme is applied to a quantum dot system. Compared with the method in Ref. [Phys. Rev. A, 84, 052116, 2011], our coherent feedback can obtain a better performance of decoherence suppression for fermion systems.