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arXiv · 2110.07825

Quantum parameter estimation in a dissipative environment

Wei Wu·Chuan Shi
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Abstract

We investigate the performance of quantum parameter estimation based on a qubit probe in a dissipative bosonic environment beyond the traditional paradigm of weak-coupling and rotating-wave approximations. By making use of an exactly numerical hierarchical equations of motion method, we analyze the influences of the non-Markovian memory effect induced by the environment and the form of probe-environment interaction on the estimation precision. It is found that (i) the non-Markovianity can effectively boost the estimation performance and (ii) the estimation precision can be improved by introducing a perpendicular probe-environment interaction. Our results indicate the scheme of parameter estimation in a noisy environment can be optimized via engineering the decoherence mechanism.

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Wei Wu, Chuan Shi. 2021-10-15. Quantum parameter estimation in a dissipative environment. https://doi.org/10.1103/physreva.102.032607

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