Cooperative electron-phonon interaction in molecular chains

Sudhakar Yarlagadda

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arXiv · 0712.0366

Cooperative electron-phonon interaction in molecular chains

Sudhakar Yarlagadda

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Abstract

Using a controlled analytic treatment, we derive a model that generically describes cooperative strong electron-phonon interaction (EPI) in one-band and two-band Jahn-Teller (JT) systems. The model involves a {\em next-nearest-neighbor} hopping and a nearest-neighbor repulsion. Rings with odd number of sites (o-rings) belong to a different universality class compared to rings with even number (e-rings). The e-rings, upon tuning repulsion, undergo a dramatic discontinuous transition to a {\em conducting commensurate} charge density wave (CDW) state with a period independent of filling.

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Sudhakar Yarlagadda. 2008-03-03. Cooperative electron-phonon interaction in molecular chains. https://arxiv.org/abs/0712.0366

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