The Study On Transport Of A Single Photon In Waveguide System

Photons are excellent information carriers in quantum information technology.The requirement for achieving novel single-photon devices is precise manipulation of single-photon transport.Waveguide-cavity-atom coupling systems make the photon-atom interaction into the strong coupling regime and provide a realizable way to develop single-photon devices and to construct quantum networks.In this thesis,a target whispering-gallery mode microresonator(WGMM) directly coupled to a waveguide with an auxiliary WGMM side coupled is proposed to deterministically extract both the resonant and the non-resonant single photons incident from the waveguide.Based on the single-photon Raman interaction(SPRINT) between a ?-type three-level atom and the target WGMM,a full quantum theory in real space is adopted to calculate the extraction efficiencies at the single-photon level.The results show that the extraction efficiencies can be significantly improved by properly tuning the frequencies of the auxiliary WGMM and the coupling strengths between the two coupled WGMMs,even when the atom and WGMMs have dissipations.As the mode redistribution is just externally imposed on the auxiliary WGMM,the population and the phase of the atom will not be affected directly.This nonlocal control ensuring the single-photon Raman interaction results in high extraction efficiencies.We also find that the transmission probabilities of both the resonant and non-resonant incident photons can be controlled from 0 to 100%,so that the present double-WGMM system has the potential to be used as a single-photon switch.Meanwhile,single-photon devices such as switches,beam splitters,and diodes are fundamental components to construct photonic integrated quantum networks.In this thesis,two V-type three-level atoms coupled to a waveguide is proposed to simultaneously realize these functions.When the two atoms are both driven by the external coherent fields,the difference in the phases of the coherent drive induces the photonic Aharonov-Bohm effect.Based on the photonic Aharonov-Bohm effect and setting the two-atom distance to match the constructive or destructive interference conditions among photons travelling along different paths,single-photon switches is achieved since the incident photon can be controlled from complete transmission to reflection by adjusting the amplitudes and phases of the driving fields.Under properly changing the amplitudes and phases,the incident photon is split equally into multiple components as beam splitters with different frequencies.Meanwhile,the single-photon diode with the configurable transmission direction can also be obtained.Based on the research in this thesis,we propose a method to precisely extract a single photon from an optical pulse by utilizing the strong coupling among waveguide-WGMM-atom.By the way,the transporting properties of single photons can also be manipulated by adjusting the phase difference between the two external driving fields.These above results in waveguide systems can be used to construct photonic quantum networks.