Coupled Superradiance Master Equations: Application to Fluctuations in Coherent Pulse Propagation in Resonant Media
Cooperative phenomena in radiation-matter interactions range from coherent pulse propagation on the one hand to superradiant emission on the other. The question of fluctuations in cooperative phenomena has received little consideration despite its importance both for stability studies of pulse propagation and for elucidating the connection between superradiance and pulse propagation. The usual procedure is to treat coherent pulse propagation and super-radiance as completely different problems in spite of the fact that the interaction Hamiltonian is the same and the effects proportional to N2 dominate in both cases. One of the main purposes of this paper is to present and discuss the results of a master-equation formalism that provides a unified treatment of coherent pulse propagation and fluctuation phenomena by splitting off and treating exactly the self-consistent part of the matter-field interaction. A second main purpose of the paper is to show how easily one may generalize existing formulations of the superradiance problem by treating dynamically the radiation field, as well as the matter,thus leading to a system of two coupled master equations for the reduced density operators of the matter and of the field.
KeywordsMaster Equation Cooperative Phenomenon Reduce Density Operator Coherent Propagation Field Moment
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Footnotes and References
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