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arXiv · 0806.0941

Photon localization and Dicke superradiance in atomic gases

E. Akkermans·A. Gero·R. Kaiser
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Abstract

Photon propagation in a gas of N atoms is studied using an effective Hamiltonian describing photon mediated atomic dipolar interactions. The density P(Γ) of photon escape rates is determined from the spectrum of the N x N random matrix Γ_{ij} = \sin (x_{ij}) / x_{ij}, where x_{ij} is the dimensionless random distance between any two atoms. Varying disorder and system size, a scaling behavior is observed for the escape rates. It is explained using microscopic calculations and a stochastic model which emphasizes the role of cooperative effects in photon localization and provides an interesting relation with statistical properties of "small world networks".

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E. Akkermans, A. Gero, R. Kaiser. 2008-06-05. Photon localization and Dicke superradiance in atomic gases. https://doi.org/10.1103/physrevlett.101.103602

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