Manipulation of asymmetric steering and periodic entanglement in cavity magnetomechanics induced by chiral exceptional points

作     者：Zhong-Hui Yuan Yan Xia Yong-Yuan Jiang Jie Song 

作者机构：School of Physics Harbin Institute of Technology Harbin 150001 China Department of Physics Fuzhou University Fuzhou 350002 China Key Laboratory of Micro-Nano Optoelectronic Information System Ministry of Industry and Information Technology Harbin 150001 China Key Laboratory of Micro-Optics and Photonic Technology of Heilongjiang Province Harbin Institute of Technology Harbin 150001 China Collaborative Innovation Center of Extreme Optics Shanxi University Taiyuan Shanxi 030006 China 

出 版 物：《Physical Review B》 (Phys. Rev. B)

年 卷 期：2025年第111卷第1期

页      面：014433-014433页

核心收录：

基　　金：Fundamental Research Funds for the Central Universities, (2023FRFK06012) National Natural Science Foundation of China, NSFC, (11675046) Harbin Institute of Technology, HIT, (A201412) Postdoctoral Scientific Research Development Fund of Heilongjiang Province, (LBH-Q15060) 

主　　题：Quantum entanglement 

摘      要：We study the periodic entanglement and asymmetric steering at exceptional points for a non-Hermitian cavity magnetomechanics system in which exceptional points (EPs) emerge periodically by controlling the relative phase angle of the nanoparticles. First, we analyze this hybrid system and identify parametric regimes where different types of entanglement and steering are enhanced. Entanglement and steering can be significantly enhanced due to the external control method and are thus more robust to thermal noises. This provides an active method to manipulate the asymmetry of steering instead of adding asymmetric losses or noises to subsystems at the cost of reducing steering ability. Moreover, the relative phase angle (RPA) not only enhances the strength of entanglement but also increases the domain of entanglement over a wider space of detunings compared to a system in which no RPA is present. Another important consequence of the RPA is that it controls the directivity of quantum steering. Specifically, steering reaches a maximal value at EPs as well, and we can get rich properties of Einstein-Podolsky-Rosen steering; e.g., the asymmetry of the overall state is stepwise, including one-way quantum steering, no-way quantum steering, and two-way quantum steering. We believe that the presented scheme is a step forward in realizing robust quantum entanglement using current technology. Our results indicate that cavity magnetomechanics systems could provide a promising platform for the study of macroscopic quantum phenomena.