Based-nonequilibrium-environment non-Markovianity, quantum Fisher information and quantum coherence

TL;DR

This paper explores how nonequilibrium environments influence non-Markovianity, quantum Fisher information, and quantum coherence in a qubit, revealing parameter effects that can enhance quantum metrology.

Contribution

It provides explicit expressions for QFI and quantum coherence in nonequilibrium environments and analyzes their dependence on noise parameters, highlighting conditions that optimize quantum effects.

Findings

Suitable environment parameters can retard QFI and coherence.

Smaller memory effects and higher jumping rates increase QFI and coherence.

Larger QFI correlates with larger quantum coherence, enhancing quantum metrology.

Abstract

In this work, we investigate the non-Markovianity, quantum Fisher information (QFI) and quantum coherence of a qubit in a nonequilibrium environment and have obtained the expressions of QFI and quantum coherence as well as their relationship. We have also discussed in detail the influences of the different noise parameters on these quantum sffects. The results show that the suitable parameters of the nonequilibrium environment can retard the QFI and quantum coherence in both Markovian and non-Markovian regions. In addition, the smaller memory effects and the larger the jumping rate, the greater the QFI and quantum coherence. And a larger QFI naturally corresponds to a larger quantum coherence, which indicates that the quantum coherence can enlarge the QFI and can effectively enhance the quantum metrology.