Finite-temperature phase diagram of hard-core bosons in two dimensions.

  title={Finite-temperature phase diagram of hard-core bosons in two dimensions.},
  author={Guido Schmid and Synge Todo and Matthias Troyer and Ansgar Dorneich},
  journal={Physical review letters},
  volume={88 16},
We determine the finite-temperature phase diagram of the square lattice hard-core boson Hubbard model with nearest neighbor repulsion using quantum Monte Carlo simulations. This model is equivalent to an anisotropic spin-1/2 XXZ model in a magnetic field. We present the rich phase diagram with a first order transition between a solid and superfluid phase, instead of a previously conjectured supersolid and a tricritical end point to phase separation. Unusual reentrant behavior with ordering upon… CONTINUE READING