含多个相干耦合人工原子的单模腔的输入输出特性  

Input-output characteristics of single-mode cavity with multiple coherently coupled artificial atoms

作　　者：郑赟杰 王晨阳 谢双媛[1] 许静平[1] 羊亚平[1] Zheng Yun-Jie;Wang Chen-Yang;Xie Shuang-Yuan;Xu Jing-Ping;Yang Ya-Ping(Key Laboratory of Advanced Micro-Structured Materials of Ministry of Education,School of Physics Science and Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学物理科学与工程学院,教育部人工微结构材料重点实验室,上海200092

出　　处：《物理学报》2022年第24期195-206,共12页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:12274326,12174288)资助的课题.

摘　　要：在以往的腔量子电动力学(QED)系统中原子气通常被处理成单个原子,从而得到诸如拉比劈裂、单光子阻塞等现象.受益于超导电路QED的发展,超导量子比特(SQUID)可以被看成人工原子,它们之间通过LC谐振子失谐的耦合会构成人工原子间的等效相干耦合.基于此,研究了具有相干耦合的多个人工原子对单模腔输入输出的影响,并从缀饰态的角度对透射谱进行了分析.结果发现包含多个相干耦合人工原子的单模腔,其透射谱与只含单个原子的腔显著不同,更重要的是透射峰的数目并不会随着人工原子数的增加而增加,最多只有3个透射峰.为了解释这种透射谱的规律,应用全量子理论,计算了整个系统在不含耗散时单能量子情况下的本征值和本征态.原则上,有几个粒子,就会形成几个缀饰态,理论上就会出现几个透射峰.然而本文发现存在一些不包含光子成分的缀饰态,它们并不贡献透射峰.而原子数增多后会出现透射峰劈裂,这对应着能级避免交叉现象,本文从缀饰态角度进行了说明.从这些缀饰态的具体形式上很多都具有多体纠缠的性质.因此采用这样一种包含多个相干耦合人工原子的单模腔,将有利于构建多体纠缠态,在未来也可以通过透射率的变化,探知腔内多体纠缠态的形式.In previous cavity quantum electrodynamics(QED)systems,atomic gas is usually treated as single atoms,thereby resulting in phenomena such as Rabi splitting,and single-photon blocking.Benefiting from the development of superconducting circuit QED,the superconducting quantum interference devices(SQUIDs)can be regarded as artificial atoms,and the detuned coupling of them through LC harmonic oscillators will constitute an equivalent coherent coupling between artificial atoms.According to this,we study the effect of multiple artificial atoms with coherent coupling on the input and output of a single-mode cavity,and analyze the transmission spectrum from the perspective of decorated state.We find that single-mode cavities containing multiple artificial atoms with coherent coupling have significantly different transmittances from cavities containing single atoms,the transmission spectra of which are correlated with the coherent coupling coefficients between the artificial atoms,and the coupling coefficients between the cavity modes and the artificial atoms,and we also find that both the cavity mode leakage rate and the artificial atom decay rate are related to each other.And as the number of artificial atoms increases,the number of transmission peaks does not increase,and there are only three transmission peaks at most.In order to explain the law of this transmission spectrum,we quantize both artificial atoms and cavity modes,and calculate the eigenvalues and eigenstates of the whole in a single quantum case.In principle,if there are several particles,they will form several decorative states,and there will theoretically appear several transmission peaks.However,we find that there are some decorated states that do not contain the photonic component and thus do not contribute to the transmission peak.From the specific form of these decorated states,many of them have the property of many-body entanglement.Therefore,using such a single-mode cavity containing multiple coherently coupled artificial atoms,we can construct the r

关 键 词：腔量子电动力学 原子间相干耦合 输入输出关系 

分 类 号：O562[理学—原子与分子物理] O413.2[理学—物理]