A mean position state based on the gauge invariant transverse vector potential is used to convert single-photon states in Hilbert space to photon wave packets in direct space. The resulting photon wave-mechanical desc...A mean position state based on the gauge invariant transverse vector potential is used to convert single-photon states in Hilbert space to photon wave packets in direct space. The resulting photon wave-mechanical description leads to scalar products which relate to covariant integration on the light cone. A new correlation matrix displays the spatial localization problem for single photons in an explicit manner in space-time. The correlation matrix essentially is the projection of the time-ordered Feynman photon propagator onto the transverse photon subspace. The present photon wave-mechanical formalism is generalized to two-photon dynamics. In the diamagnetic limit the transverse photon becomes massive in its interaction with matter, and the correlation matrix for massivephoton interaction, which can be used in studies of evanescent-photon mediated couplings, is analyzed. On the basis of the present formalism the existence of a dynamical near-field Aharonov-Bohm effect is predicted.展开更多
We study a quantum electrodynamics(QED) system made of a two-level atom and a semi-infinite rectangular waveguide, which behaves as a perfect mirror in one end. The spatial dependence of the atomic spontaneous emissio...We study a quantum electrodynamics(QED) system made of a two-level atom and a semi-infinite rectangular waveguide, which behaves as a perfect mirror in one end. The spatial dependence of the atomic spontaneous emission has been included in the coupling strength relevant to the eigenmodes of the waveguide. The role of retardation is studied for the atomic transition frequency far away from the cutoff frequencies. The atom-mirror distance introduces different phases and retardation times into the dynamics of the atom interacting resonantly with the corresponding transverse modes. It is found that the upper state population decreases from its initial as long as the atom-mirror distance does not vanish, and is lowered and lowered when more and more transverse modes are resonant with the atom. The atomic spontaneous emission can be either suppressed or enhanced by adjusting the atomic location for short retardation time.There are partial revivals and collapses due to the photon reabsorbed and re-emitted by the atom for long retardation time.展开更多
文摘A mean position state based on the gauge invariant transverse vector potential is used to convert single-photon states in Hilbert space to photon wave packets in direct space. The resulting photon wave-mechanical description leads to scalar products which relate to covariant integration on the light cone. A new correlation matrix displays the spatial localization problem for single photons in an explicit manner in space-time. The correlation matrix essentially is the projection of the time-ordered Feynman photon propagator onto the transverse photon subspace. The present photon wave-mechanical formalism is generalized to two-photon dynamics. In the diamagnetic limit the transverse photon becomes massive in its interaction with matter, and the correlation matrix for massivephoton interaction, which can be used in studies of evanescent-photon mediated couplings, is analyzed. On the basis of the present formalism the existence of a dynamical near-field Aharonov-Bohm effect is predicted.
基金Supported by National Natural Science Foundation of China under Grant Nos.11374095,11422540,11434011,and 11575058National Fundamental Research Program of China(the 973 Program)under Grant No.2012CB922103Hunan Provincial Natural Science Foundation of China under Grant No.11JJ7001
文摘We study a quantum electrodynamics(QED) system made of a two-level atom and a semi-infinite rectangular waveguide, which behaves as a perfect mirror in one end. The spatial dependence of the atomic spontaneous emission has been included in the coupling strength relevant to the eigenmodes of the waveguide. The role of retardation is studied for the atomic transition frequency far away from the cutoff frequencies. The atom-mirror distance introduces different phases and retardation times into the dynamics of the atom interacting resonantly with the corresponding transverse modes. It is found that the upper state population decreases from its initial as long as the atom-mirror distance does not vanish, and is lowered and lowered when more and more transverse modes are resonant with the atom. The atomic spontaneous emission can be either suppressed or enhanced by adjusting the atomic location for short retardation time.There are partial revivals and collapses due to the photon reabsorbed and re-emitted by the atom for long retardation time.
