Finite-temperature phase transitions in a two-dimensional boson Hubbard model

Abstract

We study finite-temperature phase transitions in a two-dimensional boson Hubbard model with zero-point quantum fluctuations via Monte Carlo simulations of quantum rotor model, and construct the corresponding phase diagram. Compressibility shows a thermally activated gapped behavior in the insulating regime. Finite-size scaling of the superfluid stiffness clearly shows the nature of the Kosterlitz-Thouless transition. The transition temperature, $T_c$, confirms a scaling relation $T_c\propto {\rho }_0^x$ with $x=1.0$. Some evidences of anomalous quantum behavior at low temperatures are presented.

4 pages, 7 figures

References in corpus (10)

• Continuous Quantum Phase Transitions
• Quantum criticality
• The superconductor-insulator transition in 2D dirty boson systems
• Finite-Temperature Phase Diagram of Hard-Core Bosons in Two Dimensions
• Criticality in correlated quantum matter
• Theory of finite temperature crossovers near quantum critical points close to, or above, their upper-critical dimension
• Cluster Monte Carlo Algorithm for the Quantum Rotor Model
• Kosterlitz-Thouless transition of quantum XY model in two dimensions
• Ground state parameters, finite-size scaling, and low-temperature properties of the two-dimensional S=1/2 XY model
• Directed geometrical worm algorithm applied to the quantum rotor model

Cited by in corpus (3)

• Ultracold bosons with short-range interaction in regular optical lattices
• Cold-atoms on a two-dimensional square optical lattice with an alternating potential
• Phase transition to Bose-Einstein condensation for a Bosonic gas confined in a combined trap