摘要
The open quantum system can be described by either a Lindblad master equation or a non-Hermitian Hamiltonian(NHH).However,these two descriptions usually have different exceptional points(EPs),associated with the degeneracies in the open quantum system.Here,considering a dissipative quantum Rabi model,we study the spectral features of EPs in these two descriptions and explore their connections.We find that,although the EPs in these two descriptions are usually different,the EPs of NHH will be consistent with the EPs of master equation in the weak coupling regime.Further,we find that the quantum Fisher information(QFI),which measures the statistical distance between quantum states,can be used as a signature for the appearance of EPs.Our study may give a theoretical guidance for exploring the properties of EPs in open quantum systems.
作者
欧先锋
黄嘉豪
李朝红
Xianfeng Ou;Jiahao Huang;Chaohong Lee(Guangdong Provincial Key Laboratory of Quantum Metrology and Sensing&School of Physics and Astronomy,Sun Yat-Sen University(Zhuhai Campus),Zhuhai 519082,China;State Key Laboratory of Optoelectronic Materials and Technologies,Sun Yat-Sen University(Guangzhou Campus),Guangzhou 510275,China;Synergetic Innovation Center for Quantum Effects and Applications,Hunan Normal University,Changsha 410081,China)
基金
Project supported by the Key-Area Research and Development Program of GuangDong Province,China (Grant No. 2019B030330001)
the National Natural Science Foundation of China (Grant Nos. 12025509, 11874434, and 11704420)
the Science and Technology Program of Guangzhou (China)(Grant No. 201904020024)
partially supported by the Guangzhou Science and Technology Projects (Grant No. 202002030459)