The Study On Transport And Routing Of Single Photon In Multiple Quantum Channels

With the sustainable development of the quantum information science quantum communication and quantum computation based on the quantum networks have gained widely attention.It is know that a quantum network consists of quantum channels and nodes.The quantum channel are mainly responsible for the photons transport.The quantum nodes are usually utilized to receive,restore and transmit the quantum information.Furthermore,there must be carrier of information.Since photons are neutral particles,there is no direct coupling between photons,and there is no strong the strong interaction with the most of the material.Besides,photons can be transmitted in long distance low loss in space and the medium.Therefore,photons are ideal candidates of carrying quantum information.In the cavity quantum electrodynamics(CQED),by controlling interaction between atoms and cavity,single photon would be freely reflected,transmitted and transferred,and the single photon transport can be implemented.Recently,there are numerous theoretical and experimental studies on single photons transport and router.However,most of these works is about,i.e.The quantum channel only includes one input and output.However,a complex quantum networks must contain more than one output,therefore,the ideal quantum router with multi-access channels is worth further exploration.There are a few studies about quantum routingof single photon with multiple quantum channels.For example,a cyclic three-level system embedded in multiple quantum channels formed with1 D CRWs can be used as a quantum router,and an external classical field containing many photons is imposed in the research models.However,there could be dissipation of photons in such cases.Thus the single photon we study in this paper is not imposed with classic field.In this paper,we mainly discuss that without the action of the additional classic field how the single photon's transport and router are proposed with two two-level atoms coupled to quantum multichannel that is made of two one-dimensional(1D)Coupled Resonator Wave-guides.The dipole-dipole interaction is supposed to between atoms.And we will also analyze how to control single photon transmission and router.In chapter 1,it states the background of the thesis,including a brief illustration of influence and effect of quantum information on single photon transmission and manipulation on quantum information.The study objective and main content are also included in the first chapter.In chapter 2,we introduce the basic theory we used in the research,including the basic concept and dynamic of cavity quantum electrodynamics,the basic theory of scattering and the processing method of quantum mechanics.An example of a two-level atom embedded in a one-dimensional coupled resonant waveguide studying the scattering properties of single photon in the waveguide transmission is also included.In chapter 3,we mainly studies the single photon transmission and router problem in multi-quantum channel.Single photon's transport and router are proposed with two single atoms coupled to quantum multi-channel that is made of two one-dimensional(1D)Coupled-Resonator Wave-guides.Dipole-dipole interaction is supposed to exist between atoms.We also analyze the scattering properties on single photon,such as transmittance and reflectance and analyses how to control single photon transmission and router.It is revealed that when there is an overlap between two bands of the CRWs,the resonant tunneling process induces the atoms to act as a multi-channel router.,While there is no overlap between the two bands,the existence of bound states makes the atoms act as a single-channel router,and in such a case single photon can be perfectly reflected or transmitted by the atoms.In chapter 4,we make a summary on the research and analyze the prospect of the quantum information.We hope that the future research of quantum information processing and quantum networks can take advantage of this paper to work out a better way of quantum information processing through changing model and scattering source.