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Journal of Physics Conference Series

Quantum correlations and laser threshold

F. Papoff, Gian Luca Lippi, Giampaolo D’Alessandro, Gian‐Luca Oppo

Published Nov 1, 2024• 0 citations
Publisher

Abstract

Abstract We present a model of nanolasers that includes the effect of all two-particle quantum correlations. We find that the lasing starts with a finite coherent amplitude and that lasing and non-lasing solutions coexist.
DOI
10.1088/1742-6596/2894/1/012010

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We derive a model for a single-mode laser that includes all two-particle quantum correlations between photons and electrons. In contrast to the predictions of semiclassical models, we find that lasing takes place in the presence of quantum bistability between a nonlasing and a nonclassical coherent state. The coherent state is characterized by a central frequency and a finite linewidth and emerges with finite amplitude from a saddle-node bifurcation together with an unstable coherent state. Hence coherent emission in nanolasers originates through a mixing of lasing and nonlasing states. In the limit of a macrolaser with a large number of emitters and nonresonant modes, the laser threshold approaches the prediction of the semiclassical theory, but with the important difference that lasing can be achieved only in the presence of finite-size perturbations.