arXiv:2012.15512 · Journal of Physics & Astronomy

Dynamics of quantum Fisher information in a squeezed thermal bath

Asghar Ullah

Published Dec 31, 2020• 0 citations

Abstract

In this paper, the dynamics of quantum Fisher information of a qubit interacting with a squeezed thermal environment are studied. The optimal initial state of the qubit, the temperature of the environment, and the interaction time, which maximize quantum Fisher information are obtained. Based on the ohmicity of the environment, we compare the dynamics of quantum Fisher information in ohmic, sub-ohmic, and super-ohmic regimes of the environment. Moreover, it is shown that the precise estimation of parameters is robust against squeezing.

DOI: 10.48550/arxiv.2012.15512

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