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arXiv · 1209.5975

Low temperature acoustic polaron localization

Riccardo Fantoni
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Abstract

We calculate the low temperature properties of an acoustic polaron in three dimensions in thermal equilibrium at a given temperature using a specialized path integral Monte Carlo method. In particular we find numerical evidence that the chosen Hamiltonian for the acoustic polaron describes a phase transition from a localized state to an unlocalized state for the electron as the phonons-electron coupling constant decreases. The phase transition manifests itself with a jump discontinuity in the potential energy as a function of the coupling constant. In the weak coupling regime the electron is in an extended state whereas in the strong coupling regime it is found in a self-trapped state.

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Riccardo Fantoni. 2012-09-26. Low temperature acoustic polaron localization. https://doi.org/10.1103/physrevb.86.144304

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