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arXiv · 0810.0665

Metal-insulator transition and strong-coupling spin liquid in the $t{-}t^\prime$ Hubbard model

Federico Becca·Luca F. Tocchio·Sandro Sorella
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Abstract

We study the phase diagram of the frustrated $t{-}t^\prime$ Hubbard model on the square lattice by using a novel variational wave function. Taking the clue from the backflow correlations that have been introduced long-time ago by Feynman and Cohen and have been used for describing various interacting systems on the continuum (like liquid $^3$He, the electron jellium, and metallic Hydrogen), we consider many-body correlations to construct a suitable approximation for the ground state of this correlated model on the lattice. In this way, a very accurate {\it ansatz} can be achieved both at weak and strong coupling. We present the evidence that an insulating and non-magnetic phase can be stabilized at strong coupling and sufficiently large frustrating ratio $t^\prime/t$.

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Federico Becca, Luca F. Tocchio, Sandro Sorella. 2008-10-03. Metal-insulator transition and strong-coupling spin liquid in the $t{-}t^\prime$ Hubbard model. https://doi.org/10.1088/1742-6596/145/1/012016

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