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A Dynamical Study of the Quantum p=2 Spherical Model

Michal Rokni·Premala Chandra
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Abstract

We present a dynamical study of the disordered quantum p=2 spherical model at long times. Its phase behavior as a function of spin-bath coupling, strength of quantum fluctuations and temperature is characterized, and we identify different paramagnetic and coarsened regions. A quantum critical point at zero temperature in the limit of vanishing dissipation is also found. Furthermore we show analytically that the fluctuation-dissipation theorem is obeyed in the stationary regime.

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Michal Rokni, Premala Chandra. 2004-03-21. A Dynamical Study of the Quantum p=2 Spherical Model. https://doi.org/10.1103/physrevb.69.094403

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