Interacting spin-1 bosons in a two-dimensional optical lattice
Abstract
We study, using quantum Monte Carlo (QMC) simulations, the ground state properties of spin-1 bosons trapped in a square optical lattice. The phase diagram is characterized by the mobility of the particles (Mott insulating or superfluid phase) and by their magnetic properties. For ferromagnetic on-site interactions, the whole phase diagram is ferromagnetic and the Mott insulators-superfluid phase transitions are second order. For antiferromagnetic on-site interactions, spin nematic order is found in the odd Mott lobes and in the superfluid phase. Furthermore, the superfluid-insulator phase transition is first or second order depending on whether the density in the Mott is even or odd. Inside the even Mott lobes, we observe a singlet-to-nematic transition for certain values of the interactions. This transition appears to be first order.
Cite
@article{arxiv.1306.5515,
title = {Interacting spin-1 bosons in a two-dimensional optical lattice},
author = {L. de Forges de Parny and F. Hébert and V. G. Rousseau and G. G. Batrouni},
journal= {arXiv preprint arXiv:1306.5515},
year = {2015}
}