近日，山西大学的张天才及其研究小组与中北大学的白成华团队合作并取得一项新进展。经过不懈努力，他们利用合成磁性实现对多个力学振子的不对称同步压缩。相关研究成果已于2023年11月21日在《物理评论A》期刊上发表。

该研究团队深入研究了空腔光力学系统中两个力学振子的同步压缩产生与控制机制。研究人员通过将两个力学振子与由双色激光驱动的光学腔耦合，并引入两种力学模式之间的相位相关声子跳跃相互作用，成功产生了合成磁性。研究人员发现两种裸力学模式之间合成磁性的存在可以打破Bogoliubov-dark模式效应，并使得两种力学模式能够同时实现强压缩，突破了传统的3dB限制。

此外，研究人员发现，通过精准调控声子跳跃相互作用的相位，可以实现两个力学振子的非对称压缩。这种不对称压缩效应源于两个Bogoliubov模式间的非互易布居数转移。该方案对热噪声具有较强的鲁棒性，可推广到多种力学模式，不仅能够实现强压缩，还能控制多个力学振子的相对压缩程度，对宏观量子效应的研究和量子精密测量具有重要意义。

附：英文原文

Title: Asymmetrical simultaneous squeezing of multiple mechanical oscillators via synthetic magnetism

Author: Qi Guo, Jinke Cao, Cheng-Hua Bai, Yuchi Zhang, Gang Li, Tiancai Zhang

Issue&Volume: 2023/11/21

Abstract: We focus on the generation and control of simultaneous squeezing for two mechanical oscillators in a cavity optomechanical system. The two mechanical oscillators couple to an optical cavity driven by two-tone lasers, and the phase-dependent phonon-hopping interaction between the two mechanical modes is introduced to create synthetic magnetism. We show that the presence of the synthetic magnetism between the two bare mechanical modes can break the Bogoliubov-dark-mode effect, and enable the strong squeezing (breaking the so-called 3-dB limit) of the two mechanical modes to be achieved simultaneously. Moreover, the asymmetrical squeezing for two mechanical oscillators can be realized by adjusting the phase of the phonon-hopping interaction. We find that the asymmetrical squeezing is caused by nonreciprocal population transfer between the two Bogoliubov modes. The presented scheme has significantly strong robustness against thermal noise, and can be extended to multiple mechanical modes to achieve strong squeezing and control the relative squeezing degree of multiple mechanical oscillators, which may be meaningful for the study of macroscopic quantum effects and quantum precision measurement.

DOI: 10.1103/PhysRevA.108.053512

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.108.053512