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Operator-sum representation of time-dependent density operators and its applications

D. M. Tong·L. C. Kwek·C. H. Oh·Jing-Ling Chen·L. Ma
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Abstract

We show that any arbitrary time-dependent density operator of an open system can always be described in terms of an operator-sum representation regardless of its initial condition and the path of its evolution in the state space, and we provide a general expression of Kraus operators for arbitrary time-dependent density operator of an $N$-dimensional system. Moreover, applications of our result are illustrated through several examples.

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D. M. Tong, L. C. Kwek, C. H. Oh, Jing-Ling Chen, L. Ma. 2004-07-15. Operator-sum representation of time-dependent density operators and its applications. https://doi.org/10.1103/physreva.69.054102

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