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Numerical study of the $E\otimes e$ Jahn-Teller polaron and bipolaron

S. El Shawish·J. Bonca·Li-Chung Ku·S. A. Trugman
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Abstract

The properties of the polaron and bipolaron are explored in the 1D Jahn-Teller model with dynamical quantum phonons. The ground-state properties of the polaron and bipolaron are computed using a recently developed variational method. Dynamical properties of the ground state of a polaron are investigated by calculating the optical conductivity $σ(ω)$. Our numerical results suggest that the Jahn-Teller and Holstein polarons are similar. However, in the strong-coupling regime qualitative differences in $σ(ω)$ between the two models are found and discussed. The influence of the electron-phonon coupling and the electrostatic repulsion on the bipolaron binding energy, bipolaron masses, and correlation functions is investigated.

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S. El Shawish, J. Bonca, Li-Chung Ku, S. A. Trugman. 2002-11-06. Numerical study of the $E\otimes e$ Jahn-Teller polaron and bipolaron. https://doi.org/10.1103/physrevb.67.014301

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