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Variational Monte Carlo studies of a t-J model on an anisotropic triangular lattice

Tsutomu Watanabe·Hisatoshi Yokoyama·Yukio Tanaka·Jun-ichiro Inoue·Masao Ogata
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Abstract

With the insulating phase of κ-(BEDT-TTF)_2X in mind, we study a t-J model on an anisotropic triangular lattice, where the hopping integral is t' in one of the three directions, using a variational Monte Carlo method. By changing the value of t'/t, we study the stability of superconducting (SC) states with d- and d+id-wave symmetries and of an antiferromagnetic (AF) state. As t'/t decreases from 1, the stable state immediately switches from the d+id wave to the d wave. The AF state is stabilized from the normal spin liquid state for t'/t\lsim 0.7 at half filling. We also take account of Nagaoka ferromagnetism and a phase separation.

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Tsutomu Watanabe, Hisatoshi Yokoyama, Yukio Tanaka, Jun-ichiro Inoue, Masao Ogata. 2004-11-29. Variational Monte Carlo studies of a t-J model on an anisotropic triangular lattice. https://doi.org/10.1016/j.physc.2005.02.042

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