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arXiv · 1102.3275

Electron Mass Enhancement due to Anharmonic Local Phonons

Kunihiro Oshiba·Takashi Hotta
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Abstract

In order to understand how electron effective mass is enhanced by anharmonic local oscillation of an atom in a cage composed of other atoms, i.e., {\it rattling}, we analyze anharmonic Holstein model by using a Green's function method. Due to the evaluation of an electron mass enhancement factor $Z$, we find that $Z$ becomes maximum when zero-point energy is comparable with potential height at which the amplitude of oscillation is rapidly enlarged. Cooperation of such quantum and rattling effects is considered to be a key issue to explain the electron mass enhancement in electron-rattling systems.

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Kunihiro Oshiba, Takashi Hotta. 2011-04-23. Electron Mass Enhancement due to Anharmonic Local Phonons. https://doi.org/10.1143/jpsjs.80sa.sa134

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