QED(quantum electrodynamics)is the QFT(quantum field theory)describing the interaction between light and matter.While conventional QED is based on TEM(transverse electromagnetic)waves,there has been increasing interes...QED(quantum electrodynamics)is the QFT(quantum field theory)describing the interaction between light and matter.While conventional QED is based on TEM(transverse electromagnetic)waves,there has been increasing interest in the theoretical and experimental exploration of LSW(longitudinal scalar waves)solutions that are often omitted in CED(classical electrodynamics)but may have physical significance in nontrivial vacuum conditions.This paper delves into the theoretical foundation of LSW,their role in QED,and the associated mathematical equations governing their dynamics.展开更多
Waveguide quantum electrodynamics(QED)system manifests an ideal platform for studying many-body physics.When multiple emitters are coupled to a common waveguide,subradiant states may arise because of the waveguide-med...Waveguide quantum electrodynamics(QED)system manifests an ideal platform for studying many-body physics.When multiple emitters are coupled to a common waveguide,subradiant states may arise because of the waveguide-mediated interaction,leading to a long lifetime because of their immunity to the waveguide modeinduced dissipation.However,they can still be influenced by local environments,which are incoherent for different emitters and cannot be canceled out through interference.Herein,a new mechanism termed energy quantum confinement effect(EQCE)is proposed in a non-Markovian waveguide QED system to suppress the local dissipation.The energy quantum is confined in the waveguide by emitters,suppressing spontaneous decay of the emitters.The EQCE makes the system partly free from local dissipation of emitters,leading to a total decay rate lower than the local decay rate.We further show that similar effect occurs spontaneously by self-interference and can be stressed by cooperative coupling,relaxing the requirement for initializing the emitters into a remotely entangled state.展开更多
Nonclassical light fields exhibit unique quantum characteristics that not only expand the scope of optical research but also provide a solid foundation for advancements in quantum technologies.In this study,we investi...Nonclassical light fields exhibit unique quantum characteristics that not only expand the scope of optical research but also provide a solid foundation for advancements in quantum technologies.In this study,we investigate a system consisting of one-^(133)Cs atom placed in a resonant cavity.Pumped by 459 nm laser light,the system generates cavity modes corresponding to the atomic 7S_(1/2)→6P_(3/2)(1470 nm)and 7S_(1/2)→6P_(1/2)(1359 nm)transitions,which are associated with the clock states of the cesium active optical clock.By analyzing the statistical and dynamical properties of the fields,we systematically explore the nonclassical behavior of the system under varying coupling strengths and cavity decay rates.We identify parameter regions where both individual fields and their cross-correlation exhibit nonclassicality,with the Cauchy-Schwarz(CS)violation coefficient R reaching a maximum of 13.9.This demonstrates the system’s ability to generate highly nonclassical photon pairs,enriching the repertoire of nonclassical light sources.展开更多
文摘QED(quantum electrodynamics)is the QFT(quantum field theory)describing the interaction between light and matter.While conventional QED is based on TEM(transverse electromagnetic)waves,there has been increasing interest in the theoretical and experimental exploration of LSW(longitudinal scalar waves)solutions that are often omitted in CED(classical electrodynamics)but may have physical significance in nontrivial vacuum conditions.This paper delves into the theoretical foundation of LSW,their role in QED,and the associated mathematical equations governing their dynamics.
基金support from the National Key Research and Development Program of China(grant 2020YFA0715000)the National Natural Science Foundation of China(grant 62075111)+2 种基金the Tsinghua University Initiative Scientific Research ProgramH.-B.S.acknowledges support from the National Natural Science Foundation of China(grant 61960206003)Tsinghua-Foshan Innovation Special Fund(grant 2021THFS0102).
文摘Waveguide quantum electrodynamics(QED)system manifests an ideal platform for studying many-body physics.When multiple emitters are coupled to a common waveguide,subradiant states may arise because of the waveguide-mediated interaction,leading to a long lifetime because of their immunity to the waveguide modeinduced dissipation.However,they can still be influenced by local environments,which are incoherent for different emitters and cannot be canceled out through interference.Herein,a new mechanism termed energy quantum confinement effect(EQCE)is proposed in a non-Markovian waveguide QED system to suppress the local dissipation.The energy quantum is confined in the waveguide by emitters,suppressing spontaneous decay of the emitters.The EQCE makes the system partly free from local dissipation of emitters,leading to a total decay rate lower than the local decay rate.We further show that similar effect occurs spontaneously by self-interference and can be stressed by cooperative coupling,relaxing the requirement for initializing the emitters into a remotely entangled state.
基金supported by CAS Project for National Time Service Center(Grant No.E239SC1101)Young Scientists in Basic Research(Grant No.YSBR-085).
文摘Nonclassical light fields exhibit unique quantum characteristics that not only expand the scope of optical research but also provide a solid foundation for advancements in quantum technologies.In this study,we investigate a system consisting of one-^(133)Cs atom placed in a resonant cavity.Pumped by 459 nm laser light,the system generates cavity modes corresponding to the atomic 7S_(1/2)→6P_(3/2)(1470 nm)and 7S_(1/2)→6P_(1/2)(1359 nm)transitions,which are associated with the clock states of the cesium active optical clock.By analyzing the statistical and dynamical properties of the fields,we systematically explore the nonclassical behavior of the system under varying coupling strengths and cavity decay rates.We identify parameter regions where both individual fields and their cross-correlation exhibit nonclassicality,with the Cauchy-Schwarz(CS)violation coefficient R reaching a maximum of 13.9.This demonstrates the system’s ability to generate highly nonclassical photon pairs,enriching the repertoire of nonclassical light sources.
基金supported by Natural Science Research Project of High Education of Anhui Province (KJ2012Z080)Young Teachers Fund of Anhui University of Science and Technology(2012QNZ13)the Talent Foundation of High Education of Anhui Province for Outstanding Youth(2009QRZ056)
基金This work was supported by the National Science Foundation of China under Grant(No.10574001)the Program of the Education Department of Anhui Province(2004kj029)+1 种基金the Talent Foundation of Anhui Universitythe Youth Program of Fu Yang Normal College under Grant(No.2005LQ03)and(No.2005LQ04)
