Nonadiabatic elimination of auxiliary modes in continuous quantum measurements

作者：Yang Huan^*; Miao Haixing; Chen Yanbei

来源：Physical Review A, 2012, 85(4): 040101.

DOI：10.1103/PhysRevA.85.040101

In quantum measurement or control processes, there are often auxiliary modes coupling to the quantum system that we are interested in-they together form a bath or an environment for the system. The bath can have finite memory (non-Markovian), and simply ignoring its dynamics (i.e., adiabatically eliminating it) will prevent us from predicting the true quantum behavior of the system. We generalize the technique introduced by Strunz et al. [Phys. Rev. Lett. 82, 1801 (1999)], and develop a formalism that allows us to eliminate the bath nonadiabatically in continuous quantum measurements, and obtain a non-Markovian stochastic master equation for the system that we focus on. This formalism also illuminates how to design the bath-acting as a quantum filter-to effectively probe interesting system observables (e.g., the quantum-nondemolition observable).

• 出版日期2012-4-19