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arXiv · 1307.2101

Continuous Measurement of a Non-Markovian Open Quantum System

A. Shabani·J. Roden·K. B. Whaley
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Abstract

Continuous quantum measurement is the backbone of various methods in quantum control, quantum metrology, and quantum information. Here, we present a generalized formulation of dispersive measurement of a complex quantum systems. We describe the complex system as an open quantum system that is strongly coupled to a non-Markovian environment, enabling the treatment of a broad variety of natural or engineered complex systems. The system is monitored via a probe resonator coupled to a broadband (Markovian) reservoir. Based on this model, we derive a formalism of Stochastic Hierarchy Equations of Motion (SHEM) describing the decoherence dynamics of the system conditioned on the measurement record. Furthermore, we demonstrate a spectroscopy method based on weak quantum measurement to reveal the non-Markovian nature of the environment, which we term weak spectroscopy.

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A. Shabani, J. Roden, K. B. Whaley. 2014-04-26. Continuous Measurement of a Non-Markovian Open Quantum System. https://doi.org/10.1103/physrevlett.112.113601

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