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arXiv · 0901.2050

Variational approach to the Caldeira-Leggett model

Javier Sabio·Fernando Sols
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Abstract

We apply the displaced-oscillator variational ansatz to the Caldeira-Leggett model for a quantum particle in a one-dimensional box described by a tight-binding chain. We focus on the case of an Ohmic environment and study the phase diagram for different chain lengths. At zero temperature there is a phase transition to a localized phase when the number of sites is even. At finite temperature, a transition from a coherent to an incoherent regime is predicted for all the chain lengths considered. Finally, the results are compared to those obtained with numerical techniques.

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Javier Sabio, Fernando Sols. 2009-01-14. Variational approach to the Caldeira-Leggett model. https://doi.org/10.1016/j.physe.2009.06.066

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