Filtering Regulation Of Two-photon Correlation In Two-level Atomic Resonance Fluorescent

Resonance fluorescence spectrum of two-level atoms generated by stimulated radiation driven by strong fields,has always been a central topic in quantum optics.This fluorescence spectrum has a three-peak band structure,and people began to investigate resonance fluorescence frequency-resolved correlation characteristics in theory since 1980s.Recently,with the development of optical frequency resolution technology,people can use filters to resolve photons of different frequencies for research.Therefore,people once again interested in the theoretical and experimental research on the resolution of photon frequen-cies effect and the manipulation of photon statistical properties by the frequency resolution process.In this paper,we first used two cavities to resolve the frequency of photons,studied the two-photon correlation characteristics of(near)resonance frequency resolution of two-level atomic resonance fluorescent.We obtain the analytical result of the two-photon frequency resolution correlation function through the weak coupling interaction of the atom-cavity,and found that the correlation characteristics of two-photon are obvious under short delay conditions.This correlation is derived from the incoherent or coherent superposition of two possible radiation processes of two-photons.For two photons from two opposite sideband,since the initial and final states of the two radiation processes are different,the two radiation processes are incoherently superimposed,so the correlation between two photons from opposite sidebands displays a bunching effect.But the two radiation processes of a photon from a sideband and a photon from the central Rayleigh line are coherent superposition,and resulting in quantum destructive interference,so the correlation between a photon from a sideband and a photon from the central Rayleigh displays antibunching.Then,we also studied the two-photon correlation characteristics of the mixed frequen-cy resolution of the two-level atomic resonance fluorescent.Now,we adjust the frequency of a cavity to the center or near the center of the central Rayleigh line and sidebands,so that both the photon from the central Rayleigh line and the sideband photons enter the cavity.Taking the cavity field frequency modulation as the center or near the center of the low-band and the central Rayleigh line as an example,we studied the two-photon correla-tion characteristics of the mixed frequency resolution of a photon from the low-band and a photon from the central Rayleigh line.And the coherent superposition of the two radiation processes produces quantum-strength interference,thus a strong correlation characteristic occurs at the center of the central Rayleigh line and the sideband.In addition to attenuation,the two-photon correlation function with mixed frequency resolution exhibits obvious oscillating behavior under the condition of short delay.