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Journal of the Optical Society of America B

Quantum–classical correspondences for atomic operators: a positive P representation approach

Li You, J. Cooper, P. Zoller

Published Oct 1, 1995• 0 citations
Publisher

Abstract

We demonstrate the successful simulation of classical stochastic differential equations obtained from the positive P phase-space technique for two-level atoms pumped by a near-resonant laser. Numerical results for both the resonance fluorescence spectrum and the absorption spectrum are compared with the exact results.
DOI
10.1364/josab.12.001774

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The relaxation process and resonance fluorescence of a two-level atom strongly driven by stochastically fluctuating laser light is studied. A laser with small intensity fluctuations about a constant mean value and a diffusing phase is assumed. Depending on the relative time scales of the intensity fluctuations and the atomic response to these fluctuations, the time decay of the atomic population is found to be non-exponential. The broadening of the sidebands in the triplet spectrum of resonance fluorescence is shown to be non-Lorentzian.
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Calculation of spectral characteristics of small dimension quantum systems is important for quantum optics, because it gives the opportunity to bind theoretical approaches for the description of these systems and experimental data. In present work, we consider the obtaining of the autocorrelation function and the resonance fluorescence spectrum of the three-level system in stochastic Schroedinger equation approach for each individual transition and for the whole system. We provide also results of the numerical simulation for the Markovian dynamics of the system and the resonance fluorescence spectrum for the one of transitions.