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Non-Markovian dynamics of a qubit

Sabrina Maniscalco·Francesco Petruccione
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Abstract

In this paper we investigate the non-Markovian dynamics of a qubit by comparing two generalized master equations with memory. In the case of a thermal bath, we derive the solution of the post-Markovian master equation recently proposed in Ref. [A. Shabani and D.A. Lidar, Phys. Rev. A {\bf 71}, 020101(R) (2005)] and we study the dynamics for an exponentially decaying memory kernel. We compare the solution of the post-Markovian master equation with the solution of the typical memory kernel master equation. Our results lead to a new physical interpretation of the reservoir correlation function and bring to light the limits of usability of master equations with memory for the system under consideration.

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Sabrina Maniscalco, Francesco Petruccione. 2006-02-08. Non-Markovian dynamics of a qubit. https://doi.org/10.1103/physreva.73.012111

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