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Phase-space analysis of bosonic spontaneous emission

M. K. Olsen·L. I. Plimak·S. Rebic·A. S. Bradley
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Abstract

We present phase-space techniques for the modelling of spontaneous emission in two-level bosonic atoms. The positive-P representation is shown to give a full and complete description and can be further developed to give exact treatments of the interaction of degenerate bosons with the electromagnetic field in a given experimental situation. The Wigner representation, even when truncated at second order, is shown to need a doubling of the phase-space to allow for a positive-definite diffusion matrix in the appropriate Fokker-Planck equation and still fails to agree with the full quantum results of the positive-P representation. We show that quantum statistics and correlations between the ground and excited states affect the dynamics of the emission process, so that it is in general non-exponential.

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M. K. Olsen, L. I. Plimak, S. Rebic, A. S. Bradley. 2005-05-03. Phase-space analysis of bosonic spontaneous emission. https://doi.org/10.1016/j.optcom.2005.06.006

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