Quantum Monte Carlo simulations of bosonic and fermionic impurities in a two-dimensional hard-core boson system

Abstract

A two-dimensional lattice hard-core boson system with a small fraction of bosonic or fermionic impurity particles is studied. The impurities have the same hopping and interactions as the dominant bosons and their effects are solely due to quantum statistics. Quantum Monte Carlo simulations are carried out in which paths of the dominant boson species are sampled and a summation is performed over all second-species paths compatible with the permutation cycles. Both kinds of impurities reduce modestly and equally the Kosterliz-Thouless superfluid transition temperature. However, the effective impurity interactions are found to be qualitatively different at lower temperatures; fermions are repulsive and further suppress superfluidity at low temperatures.

4 pages, 5 figures

References in corpus (6)

• Many-Body Physics with Ultracold Gases
• Bose-Fermi Mixtures in a Three-dimensional Optical Lattice
• Localization of bosonic atoms by fermionic impurities in a 3d optical lattice
• Mixtures of Bosonic and Fermionic Atoms in Optical Lattices
• Competing Orders in two-dimensional Bose-Fermi mixtures
• Bose-Fermi mixtures in an optical lattice

Cited by in corpus (1)

• Generalized Dynamical Mean-Field Theory for Bose-Fermi Mixtures in Optical Lattices