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arXiv · 0805.2556

Trapping of lattice polarons by impurities

J. P. Hague·P. E. Kornilovitch·A. S. Alexandrov
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Abstract

We consider the effects of single impurities on polarons in three-dimensions (3D) using a continuous time quantum Monte-Carlo algorithm. An exact treatment of the phonon degrees of freedom leads to a very efficient algorithm and we are able to compute the polaron dynamics on an infinite lattice using an auxiliary weighting scheme. The magnitude of the impurity potential, the electron-phonon coupling and the phonon frequency are varied. We determine the magnitude of the impurity potential required for polaron trapping. For small electron-phonon coupling the number of phonons increases dramatically on trapping. The polaron binding diagram is computed, showing that intermediate-coupling low-phonon-frequency polarons are localized by exceptionally small impurities.

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J. P. Hague, P. E. Kornilovitch, A. S. Alexandrov. 2008-05-16. Trapping of lattice polarons by impurities. https://doi.org/10.1103/physrevb.78.092302

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