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arXiv · 0805.1476

Role of backflow correlations for the non-magnetic phase of the t-t' Hubbard model

Luca F. Tocchio·Federico Becca·Alberto Parola·Sandro Sorella
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Abstract

We introduce an efficient way to improve the accuracy of projected wave functions, widely used to study the two-dimensional Hubbard model. Taking the clue from the backflow contribution, whose relevance has been emphasized for various interacting systems on the continuum, we consider many-body correlations to construct a suitable approximation for the ground state at intermediate and strong couplings. In particular, we study the phase diagram of the frustrated $t{-}t^\prime$ Hubbard model on the square lattice and show that, thanks to backflow correlations, an insulating and non-magnetic phase can be stabilized at strong coupling and sufficiently large frustrating ratio $t^\prime/t$.

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Luca F. Tocchio, Federico Becca, Alberto Parola, Sandro Sorella. 2008-05-10. Role of backflow correlations for the non-magnetic phase of the t-t' Hubbard model. https://doi.org/10.1103/physrevb.78.041101

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