光机械系统中量子随机共振现象的相干反馈控制及其应用

随机共振是一种有趣的非线性现象。它通过适量噪声和外加信号在非线性系统中的合作作用，将噪声能量向信号转移，从而实现噪声辅助的信号放大。凭此，随机共振被广泛应用于放大和检测淹没于噪声背景的微弱信号。近年来，人们将随机共振的研究拓展到量子领域，正逐渐揭晓量子噪声诱导的随机共振即量子随机共振的物理机制并探索其应用。虽然量子随机共振的理论研究进展显著，但由于量子信号极其微弱而量子噪声难以控制，挑战远胜经典情况。因此，人们未能实验上实现随机共振对量子系统的有益作用。鉴于此，本项目旨在提出增强量子随机共振效应的新方案，使其在量子领域发挥有效作用。我们拟开展如下研究；1.以光机械系统为研究载体，利用相干反馈来增强量子随机共振，并将其应用到量子信号的高效探测；2.在无外加信号情况下，探讨纯量子噪声诱导的自发随机共振即相干共振现象，并加入相干反馈来增强此效应，探索在增强量子相干性和采集真空能量等方面的应用

Stochastic resonance (SR) is an interesting nonlinear phenomenon, whereby energy can be transferred from noisy background to an external signal with the cooperation of matched noise and signal, resulting in the amplification of a signal. SR has been widely applied to amplify and detect weak signals buried in noises. Recently, researchers have extended the investigation of SR to the quantum domain in order to explore the mechanism of quantum SR and its applications in quantum signal processing. Although significant progress has been made in theoretical study of quantum SR, its applications in quantum systems have not been realized experimentally, since it is too challenging to extract faint quantum signals buried in uncontrollable quantum noise. Motivated by this fact, we propose a new mechanism to enhance quantum SR effect, aiming to make it feasible to be applied in quantum systems. Our proposal includes the following two parts: 1.we investigate the enhancement of quantum SR in an optomechanical system by using coherent feedback control and its application in improving the efficiency of quantum signal detection; 2. in the absence of external signal, we study pure quantum noise induced internal SR or coherence resonance (CR) and discuss the influence of coherent feedback on quantum CR and its applications in sustaining quantum coherence and harvesting vacuum energy.