Phase separation at all interaction strengths in the t-J model

C. Stephen Hellberg; E. Manousakis

doi:10.1103/physrevlett.78.4609

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arXiv · cond-mat/9611195

Phase separation at all interaction strengths in the t-J model

C. Stephen Hellberg·E. Manousakis

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Abstract

We investigate the phase diagram of the two-dimensional t-J model using a recently developed Green's Function Monte Carlo method for lattice fermions. We use the technique to calculate exact ground-state energies of the model on large lattices. In contrast to many previous studies, we find the model phase separates for all values of J/t. In particular, it is unstable at the hole dopings and interaction strengths at which the model was thought to describe the cuprate superconductors.

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C. Stephen Hellberg, E. Manousakis. 1997-04-10. Phase separation at all interaction strengths in the t-J model. https://doi.org/10.1103/physrevlett.78.4609

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