Copyright The American Physical Society 1999. All rights reserved. Except as provided under U.S. copyright law, this work may not be reproduced, resold, distributed or modified without the express permission of The American Physical Society. The archivial version of this work was published in Phys. Rev. B 60(1), 299-307 (July 1, 1999). PRB online - Relevant Issue, 60(1) - This paperTo properly read some greek symbols on this page, you will need to have a Symbol font installed. Mobility of an electron
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The interaction of a free electron with a polar lattice possessing more than one infrared-active optical-phonon mode is considered. From the full Lagrangian describing the electron-lattice system in the presence of an applied field we derive an effective electron-phonon coupling constant and an effective longitudinal optical-phonon frequency that we argue give accurate predictions when used in the extensive, existing polaron theo-ries. We apply this formalism to the strongly coupled large polaron of Bi12SiO20 , where the Boltzmann equation cannot apply. We calculate a theoretical prediction for the large polaron mobility as a function of temperature which gives good agreement with experiment. We determine the temperature dependence of Feynman's variational parameters v and w to assist in our predictions. |