From Dicke to Anderson: Interplay of Superradiance and Disorder

Alberto Biella

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arXiv · 1407.6562

From Dicke to Anderson: Interplay of Superradiance and Disorder

Alberto Biella

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Abstract

Using a non-Hermitian Hamiltonian approach to open systems, we study the interplay of disorder and superradiance in a one- and three-dimensional Anderson model. Analyzing the complex eigenvalues of the non-Hermitian Hamiltonian, a transition to a superradiant regime is shown to occur. As an effect of openness the structure of eigenstates undergoes a strong change in the superradiant regime: we show that the sensitivity to disorder of the superradiant and the subradiant subspaces is very different; superradiant states remain delocalized as disorder increases, while subradiant states are sensitive to the degree of disorder.

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Alberto Biella. 2014-07-24. From Dicke to Anderson: Interplay of Superradiance and Disorder. https://arxiv.org/abs/1407.6562

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