Possibility of direct Mott insulator-to-superfluid transitions in weakly disordered boson systems

@article{Park1999PossibilityOD,
  title={Possibility of direct Mott insulator-to-superfluid transitions in weakly disordered boson systems},
  author={Sung Yong Park and Ji-Woo Lee and Min-Chul Cha and M.Y. Choi and B. J. Kim and Doochul Kim},
  journal={arXiv: Condensed Matter},
  year={1999}
}
We study the zero-temperature phase transitions of a two-dimensional disordered boson Hubbard model at incommensurate boson densities. Via matrix diagonalization and quantum Monte Carlo simulations, we construct the phase diagram and evaluate the correlation length exponent nu. In the presence of weak disorder, we obtain nu=0.5 +- 0.1, the same value as that in the pure model, near the tip of a Mott insulator lobe, using the dynamical critical exponent z=2. As the strength of disorder is… 
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