Condensed Matter Physics, 2015, vol. 18, No. 4, 43702
DOI:10.5488/CMP.18.43702           arXiv:1512.07798

Title: Phase transitions in Bose-Fermi-Hubbard model in the heavy fermion limit: Hard-core boson approach
Author(s):
  I.V. Stasyuk (Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine, 1 Svientsitskii St., 79011 Lviv, Ukraine) ,
  V.O. Krasnov (Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine, 1 Svientsitskii St., 79011 Lviv, Ukraine)

Phase transitions are investigated in the Bose-Fermi-Hubbard model in the mean field and hard-core boson approximations for the case of infinitely small fermion transfer and repulsive on-site boson-fermion interaction. The behavior of the Bose-Einstein condensate order parameter and grand canonical potential is analyzed as functions of the chemical potential of bosons at zero temperature. The possibility of change of order of the phase transition to the superfluid phase in the regime of fixed values of the chemical potentials of Bose- and Fermi-particles is established. The relevant phase diagrams are built.

Key words: Bose-Fermi-Hubbard model, hard-core bosons, Bose-Einstein condensate, phase transitions, phase diagrams
PACS: 71.10 Fd, 71.38


Full text [pdf] << List of papers