Quantum phase transition in an atomic Bose gas with a Feshbach resonance

M. W. J. Romans; R. A. Duine; Subir Sachdev; H. T. C. Stoof

doi:10.1103/physrevlett.93.020405

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Quantum phase transition in an atomic Bose gas with a Feshbach resonance

M. W. J. Romans·R. A. Duine·Subir Sachdev·H. T. C. Stoof

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Abstract

We show that in an atomic Bose gas near a Feshbach resonance a quantum phase transition occurs between a phase with only a molecular Bose-Einstein condensate and a phase with both an atomic and a molecular Bose-Einstein condensate. We show that the transition is characterized by an Ising order parameter. We also determine the phase diagram of the gas as a function of magnetic field and temperature: the quantum critical point extends into a line of finite temperature Ising transitions.

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M. W. J. Romans, R. A. Duine, Subir Sachdev, H. T. C. Stoof. 2003-12-18. Quantum phase transition in an atomic Bose gas with a Feshbach resonance. https://doi.org/10.1103/physrevlett.93.020405

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