Enhancement in temperature sensing of a reservoir by Kerr-nonlinear resonator

TL;DR

This paper proposes a quantum thermometry method using a Kerr-nonlinear resonator, demonstrating enhanced temperature measurement precision through increased nonlinearity and optimized detection strategies.

Contribution

It introduces a novel estimation technique leveraging Kerr nonlinearity and drive to improve quantum reservoir temperature sensing.

Findings

Enhanced precision with higher Kerr nonlinearity and drive amplitude.

Homodyne detection outperforms heterodyne detection for this scheme.

Analysis of probe purity reveals physical mechanisms behind improved sensing.

Abstract

The challenge of developing high-precision temperature sensors is an important issue that has recently received a lot of attention. In this work, we introduce an estimation technique to precisely measure the temperature of a quantum reservoir using a Kerr-nonlinear resonator with drive. Thermalization in our suggested protocol is assessed using Uhlmann-Jozsa fidelity, and then we utilize quantum Fisher information to evaluate the metrological potential of our thermometry scheme. We observe that increasing the Kerr nonlinearity coefficient and driving amplitude significantly enhances precision in the temperature estimation. Furthermore, we also explore the underlying physical mechanisms by analyzing probe purity in the steady state and evaluating the performance of homodyne versus heterodyne detection methods. Our results demonstrate that neither of these Gaussian measurements is optimal; instead, optimal homodyne detection always surpasses heterodyne detection.