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Tunable single photon and two-photon emission in a four-level quantum dot-bimodal cavity system

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 Added by Xiang Cheng
 Publication date 2019
  fields Physics
and research's language is English




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We investigate the generation of single photons and photon pairs in a cavity quantum electrodynamics system of a four-level quantum dot coupled to bimodal cavity. By tuning frequencies and intensity ratio of the driving lasers, sub-Poissonian and super-Poissonian photon statistics are obtained in each nondegenerate cavity mode respectively. Single photon emission is characterized as zero-delay second-order correlation function g^2(0)~0.15. Photon pair emission under the two-photon resonance excitation is quantified by Mandel parameter as Q~0.04. The mean cavity photon number in both scenarios can maintain large around 0.1. As a result, single photon emission and two-photon emission can be integrated in our proposed system only by tuning the external parameters of the driving lasers.



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