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arXiv · 1206.5358

Bosonic t-J Model in a stacked triangular lattice and its phase diagram

Keisuke Kataoka·Yoshihito Kuno·Ikuo Ichinose
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Abstract

In this paper, we study phase diagram of a system of two-component hard-core bosons with nearest-neighbor (NN) pseudo-spin antiferromagnetic (AF) interactions in a stacked triangular lattice. Hamiltonian of the system contains three parameters one of which is the hopping amplitude $t$ between NN sites, and the other two are the NN pseudo-spin exchange interaction $J$ and the one that measures anisotropy of pseudo-spin interactions. We investigate the system by means of the Monte-Carlo simulations and clarify the low-temperature phase diagram. In particular, we are interested in how the competing orders, i.e., AF order and superfluidity, are realized, and also whether supersolid forms as a result of hole doping into the state of the $\sqrt{3}\times \sqrt{3}$ pseudo-spin pattern with the $120^o$ structure.

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Keisuke Kataoka, Yoshihito Kuno, Ikuo Ichinose. 2012-10-31. Bosonic t-J Model in a stacked triangular lattice and its phase diagram. https://doi.org/10.1143/jpsj.81.124502

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