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arXiv · 1406.3072

Strongly bound yet light bipolarons for double-well electron-phonon coupling

Clemens PJ Adolphs·Mona Berciu
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Abstract

We use the Momentum Average approximation (MA) to study the ground-state properties of strongly bound bipolarons in the double-well electron-phonon (el-ph) coupling model, which describes certain intercalated lattices where the linear term in the el-ph coupling vanishes due tosymmetry. We show that this model predicts the existence of strongly bound yet lightweight bipolarons in some regions of the parameter space. This provides a novel mechanism for the appearance of such bipolarons, in addition to long-range el-ph coupling and special lattice geometries.

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Clemens PJ Adolphs, Mona Berciu. 2014-06-11. Strongly bound yet light bipolarons for double-well electron-phonon coupling. https://doi.org/10.1103/physrevb.90.085149

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