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arXiv · 0907.0838

On the finite size behavior of quantum collective spin systems

Giuseppe Liberti·Franco Piperno·Francesco Plastina
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Abstract

We discuss the finite size behavior of the adiabatic Dicke model, describing the collective coupling of a set of N-two level atoms (qubits) to a faster (electromagnetic) oscillator mode. The energy eigen-states of this system are shown to be directly related to those of another widely studied collective spin model, the uniaxial one. By employing an approximate continuum approach, we obtain a complete characterization of the properties of the latter, which we then use to evaluate the scaling properties of various observables for the original Dicke model near its quantum phase transition.

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Giuseppe Liberti, Franco Piperno, Francesco Plastina. 2009-07-05. On the finite size behavior of quantum collective spin systems. https://doi.org/10.1103/physreva.81.013818

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