三模光力腔中机械振子的基态冷却  

Ground State Cooling of the Mechanical Resonator in Three-Mode Optomechanical Cavity

作　　者：刘妮[1] 常瑞 张小芳[1] 梁九卿[1] LIU Ni;CHANG Rui;ZHANG Xiaofang;LIANG Jiuqing(Institute of Theoretical Physics,State Key Laboratory of Quantum Optics and Quantum Optics Devices,Shanxi University,Taiyuan 030006,China)

机构地区：[1]山西大学理论物理研究所,量子光学与光量子器件国家重点实验室,山西太原030006

出　　处：《山西大学学报（自然科学版）》2022年第1期151-156,共6页Journal of Shanxi University(Natural Science Edition)

基　　金：国家自然科学基金(11772177,12047571);山西省高等学校科技创新项目(2019L0069)。

摘　　要：基于海森堡-朗之万方程,文章首先得到三模光力腔的有效哈密顿量,并且通过对光压涨落谱、冷却率和稳态平均声子数的探究,发现当机械振子的冷却跃迁速率和加热跃迁速率分别对应于光压涨落谱的最大值和最小值时,机械振子可以很好地被冷却。通过调控参数来加强光压涨落谱的正频部分并抑制其负频部分,此时对应的冷却率达到最大,同时机械振子的稳态平均声子数远小于一,系统达到冷却。该现象使得三模光力腔系统可以广泛应用于量子通信和量子信息处理。By Heisenberg-Langevan equation,the effective Hamiltonian of three-mode optmechanical cavity was obtained.By exploring the optical fluctuation spectrum,the cooling rate and the steady-state mean phonon number,we find that the mechanical resonator is cooled well when the cooling and heating transition rate respectively corresponds to the maximum and minimum value of the optical fluctuation spectrum.In order to make the system cool,we need to strengthen the positive-frequency part and suppress the negative-frequency part,in which the corresponding cooling rate reaches the maximum.Meanwhile,the steady-state mean phonon number of the mechanical resonator is far less than one,which means it is cooled.This phenomenon makes that three-mode optomechanical cavity are widely used in quantum communication and quantum information processing.

关 键 词：三模光力腔系统 海森堡-朗之万方程 光压涨落谱 冷却率 稳态平均声子数 

分 类 号：O413[理学—理论物理]