Quantum Chaos Triggered by Precursors of a Quantum Phase Transition: The Dicke Model

C. Emary; T. Brandes

doi:10.1103/physrevlett.90.044101

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Quantum Chaos Triggered by Precursors of a Quantum Phase Transition: The Dicke Model

C. Emary·T. Brandes

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Abstract

We consider the Dicke Hamiltonian, a simple quantum-optical model which exhibits a zero-temperature quantum phase transition. We present numerical results demonstrating that at this transition the system changes from being quasi-integrable to quantum chaotic. By deriving an exact solution in the thermodynamic limit we relate this phenomenon to a localisation-delocalisation transition in which a macroscopic superposition is generated. We also describe the classical analogues of this behaviour.

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C. Emary, T. Brandes. 2003-03-06. Quantum Chaos Triggered by Precursors of a Quantum Phase Transition: The Dicke Model. https://doi.org/10.1103/physrevlett.90.044101

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