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arXiv · 1304.3007

An analysis of the $t_2-V$ model

A. Ghosh·S. Yarlagadda
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Abstract

We study a model (i.e., the $t_2-V$ model involving {\em next-nearest-neighbor hopping} and nearest-neighbor repulsion) in one-dimension that generically depicts the dominant transport mechanism in cooperative strong electron-phonon interaction systems. Using analytic and numerical approaches, hard-core-bosons are shown to typically undergo a striking discontinuous transition from a superfluid to a supersolid. Topological inequivalence of rings with even and odd number of sites is manifested through observable differences (in structure factor peaks) at the transition. Connections are also identified between the $t_2-V$ model and other topologically interesting models.

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A. Ghosh, S. Yarlagadda. 2014-07-13. An analysis of the $t_2-V$ model. https://doi.org/10.1103/physrevb.90.045140

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