Effects of counter-rotating-wave terms on the noisy frequency estimation

TL;DR

This paper explores how counter-rotating-wave terms influence the precision of noisy quantum frequency estimation, revealing they can enhance performance in certain coupling regimes and guiding high-precision quantum measurement design.

Contribution

It systematically studies the impact of counter-rotating-wave terms on noisy quantum metrology beyond perturbative methods, highlighting their beneficial effects in intermediate and strong coupling regimes.

Findings

Counter-rotating-wave terms boost quantum metrological performance.

Enhanced precision in intermediate and strong coupling regimes.

Guidelines for designing high-precision quantum estimation under decoherence.

Abstract

We investigate the problem of estimating the tunneling frequency of a two-level atomic system embedded in a dissipative environment by employing a numerically rigorous hierarchical equations of motion method. The effect of counter-rotating-wave terms on the attainable precision of the noisy quantum metrology is systematically studied beyond the usual framework of perturbative treatments. We find the counter-rotating-wave terms are able to boost the noisy quantum metrological performance in the intermediate and strong coupling regimes, whether the dissipative environment is composed of bosons or fermions. The result presented in this paper may pave a guideline to design a high-precision quantum estimation scenario under practical decoherence.