近日，宁波大学的张成杰&陈炯及其研究团队取得一项新进展。经过不懈努力，他们揭示基于萨格纳克效应诱导对称破缺的信噪比增强机制。相关研究成果已于2024年10月30日在国际知名学术期刊《物理评论A》上发表。

本文研究了光机械角速度检测装置中的这一限制问题。通过进一步分析频域内的系统动力学，研究人员发现经典的萨格纳克效应可以有效消除信号与噪声之间的不可区分性，从而在检测系统中引发对称破缺响应。在这种情况下，即使萨格纳克效应的强度远低于输入噪声，信噪比（SNR）也能显著提升。

研究人员通过定义一个标准来量化对称破缺的程度，从而阐释了SNR增强的机制。此外，他们还讨论了该方案的可行性，为通过打破信号与噪声之间的不可区分性来提高检测精度提供了一条途径。

据悉，传统的量子检测设备无法区分输入信号与伴随的噪声，这种不可区分性构成了检测系统的一种响应对称性，而检测精度则受限于初始的信噪比（SNR）。

附：英文原文

Title: Signal-to-noise-ratio amplification based on symmetry breaking induced by the Sagnac effect

Author: Wen-Zhao Zhang, Wen-Quan Yang, Jiong Cheng, Cheng-Jie Zhang

Issue&Volume: 2024/10/30

Abstract: A conventional quantum detection device is unable to distinguish between an input signal and the accompanying noise. This kind of indistinguishability forms a response symmetry to the detection system, and the detection accuracy is limited by the initial signal-to-noise ratio (SNR). We study this limiting problem in an optomechanical angular velocity detection device. By further analyzing the system dynamics in the frequency domain, we find that the indistinguishability between signal and noise can be effectively eliminated by the classical Sagnac effect, which induces the symmetry-breaking response to the detection system. In this case, the SNR can be significantly enhanced, even if the strength of the Sagnac effect is much lower than the input noise. The mechanism of SNR enhancement is illustrated by defining a criterion to quantify the degree of symmetry breaking. In addition, the feasibility of the scheme is also discussed, which offers a path to improve the detection accuracy by breaking the indistinguishability between the signal and noise.

DOI: 10.1103/PhysRevA.110.043721

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.110.043721