Phase diagram of ultracold atoms on optical lattice: Comparative study to slave fermion and slave boson for Bose Hubbard modelPhase diagram of ultracold atoms in optical lattices: Comparative study of slave fermion and slave boson approaches to Bose-Hubbard model

Abstract

We perform a comparative study of the finite temperature behavior of ultracold Bose atoms in optical lattices by the slave fermion and the slave boson approaches to the Bose Hubbard model. The phase diagram of the system is presented. Although both approaches are equivalent without approximations, the mean field theory based on the slave fermion technique is quantitatively more appropriate. Conceptually, the slave fermion approach automatically excludes the double occupancy of two identical fermions on the same lattice site. By comparing to known results in limiting cases, we find the slave fermion approach better than the slave boson approach. For example, in the non-interacting limit, the critical temperature of the superfluid-normal liquid transition calculated by the slave fermion approach is closer to the well-known ideal Bose gas result. At zero-temperature limit of the critical interaction strength from the slave fermion approach is also closer to that from the direct calculation using a zero-temperature mean field theory.

7 pages, 5 figures, published in Phys. Rev. A. Typos are corrected

References in corpus (1)

• Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms

Cited by in corpus (13)

• Dynamical Mean Field Theory for the Bose-Hubbard Model
• Bose-Fermi mixtures in an optical lattice
• Visibility of Cold Atomic Gases in Optical Lattices for Finite Temperatures
• Finite-temperature effects on the number fluctuation of ultracold atoms across the Superfluid to Mott-insulator transition
• Finite-temperature effects on the superfluid Bose-Einstein condensation of confined ultracold atoms in three-dimensional optical lattices
• Bose - Einstein Condensate Superfluid-Mott Insulator Transition in an Optical Lattice
• Phases and collective modes of hardcore Bose-Fermi mixture in an optical lattice
• Slave particle approach to the finite temperature properties of ultracold Bose gases in optical lattices
• The large coordination number expansion of a lattice Bose gas at finite temperature
• Renormalization group approach to spinor Bose-Fermi mixtures in a shallow optical lattice
• Leading-Order Auxiliary Field Theory of the Bose-Hubbard Model
• Strong-coupling RPA theory of a Bose gas near the superfluid--Mott-insulator transition: universal thermodynamics and two-body contact
• Short-range coherence of a lattice Bose atom gas in the Mott insulating phase