Estimation precision of the acceleration for a two-level atom coupled to fluctuating vacuum electromagnetic fields

TL;DR

This paper investigates how the quantum Fisher information related to acceleration evolves over time for a two-level atom interacting with electromagnetic vacuum fluctuations, revealing unique features compared to scalar fields.

Contribution

It provides the first analysis of quantum Fisher information dynamics for a two-level atom coupled to electromagnetic vacuum fields, highlighting differences from scalar field cases.

Findings

Quantum Fisher information exhibits maxima and minima during evolution.

Initial state parameter influences early quantum Fisher information.

Quantum Fisher information stabilizes over time despite different field interactions.

Abstract

In open quantum systems, we study the quantum Fisher information of acceleration for a uniformly accelerated two-level atom coupled to fluctuating electromagnetic fields in the Minkowski vacuum. With the time evolution, for the initial atom state parameter $\theta\neq\pi$, the quantum Fisher information can exist a maximum value and a local minimum value before reaching a stable value. In addition, in a short time, the quantum Fisher information varies with the initial state parameter, and the quantum Fisher information can take a maximum value at $\theta=0$. The quantum Fisher information may exist two peak values at a certain moment. These features are different from the massless scalar fields case. With the time evolution, $F_{max}$ firstly increases, then decreases, and finally, reaches the same value. However, $F_{max}$ will arrive at a stable maximum value for the case of the massless scalar fields. Although the atom response to the vacuum fluctuation electromagnetic fields is different from the case of massless scalar fields, the quantum Fisher information eventually reaches a stable value.