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Variational description of Mott insulators

Manuela Capello·Federico Becca·Michele Fabrizio·Sandro Sorella·Erio Tosatti
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Abstract

The Gutzwiller wave function for a strongly correlated model can, if supplemented with a long-range Jastrow factor, provide a proper variational description of Mott insulators, so far unavailable. We demonstrate this concept in the prototypical one-dimensional $t-t^\prime$ Hubbard model, where at half filling we reproduce all known phases, namely the ordinary Mott undimerized insulator with power-law spin correlations at small $t^\prime/t$, the spin-gapped metal above a critical $t^\prime/t$ and small $U$, and the dimerized Mott insulator at large repulsion.

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Manuela Capello, Federico Becca, Michele Fabrizio, Sandro Sorella, Erio Tosatti. 2004-12-16. Variational description of Mott insulators. https://doi.org/10.1103/physrevlett.94.026406

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