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The $E\otimes e$ Jahn-Teller Polaron in Comparison with the Holstein Polaron

Yasutami Takada
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Abstract

Based on an exact expression for the self-energy of the Jahn-Teller polaron, we find that symmetry of pseudospin rotation makes the vertex correction much less effective than that for the Holstein polaron. This ineffectiveness brings about a smaller effective mass m^* and a quantitatively differenent large-to-small polaron crossover, as examined by exact diagonalization in a two-site system. In the strong-coupling and antiadiabatic region, a rigorous analytic expression is found for m^*.

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Yasutami Takada. 1999-11-25. The $E\otimes e$ Jahn-Teller Polaron in Comparison with the Holstein Polaron. https://doi.org/10.1103/physrevb.61.8631

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