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Maximally Robust Unravelings of Quantum Master Equations

H. M. Wiseman·J. A. Vaccaro
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Abstract

The stationary solution ρof a quantum master equation can be represented as an ensemble of pure states in a continuous infinity of ways. An ensemble which is physically realizable through monitoring the system's environment we call an `unraveling'. The survival probability S(t) of an unraveling is the average probability for each of its elements to be unchanged a time t after cessation of monitoring. The maximally robust unraveling is the one for which S(t) remains greater than the largest eigenvalue of ρfor the longest time. The optical parametric oscillator is a soluble example.

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H. M. Wiseman, J. A. Vaccaro. 1997-09-07. Maximally Robust Unravelings of Quantum Master Equations. https://doi.org/10.1016/s0375-9601(98)00774-9

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