We numerically studied internal structure of Mott insulating state of Bose–Fermi mixture systems on a one-dimensional optical lattice by using quantum Monte Carlo simulations. We looked for Mott state carefully adjusting various parameters to prevent phase separation. From the calculation of density–density correlation functions we found a quasi long-range order in the particle distribution in the Mott state. The order was strongly dependent of the ratio of the number of the bosons to that of the fermions. For example, the bosons and the fermions showed a tendency of aligning alternately when equal number of the bosons and fermions are introduced in the system. The observation of the quasi long-range order in the one-dimensional system indicates the presence of true long-range order in Bose–Fermi mixtures on a three-dimensional optical lattice.We numerically studied internal structure of Mott insulating state of Bose–Fermi mixture systems on a one-dimensional optical lattice by using quantum Monte Carlo simulations. We looked for Mott state carefully adjusting various parameters to prevent phase separation. From the calculation of density–density correlation functions we found a quasi long-range order in the particle distribution in the Mott state. The order was strongly dependent of the ratio of the number of the bosons to that of the fermions. For example, the bosons and the fermions showed a tendency of aligning alternately when equal number of the bosons and fermions are introduced in the system. The observation of the quasi long-range order in the one-dimensional system indicates the presence of true long-range order in Bose–Fermi mixtures on a three-dimensional optical lattice.

Journal of the Physical Society of JapanJun 10, 20091 citation

Low temperature transitions of a two dimensional bose system

L. Reatto

Physics Letters AMar 1, 19684 citations

Hidden long-range order in a two-dimensional spin-orbit coupled Bose gas

Shih-Wei Su, I-Kang Liu, Shih-Chuan Gou +3 more

A two-dimensional spin-orbit coupled Bose gas is shown to simultaneously possess quasi and true long-range orders in the total and relative phases, respectively. The total phase undergoes a conventional Berenzinskii- Kosterlitz-Thouless transition, where an quasi long-range order is expected. Additionally, the relative phase undergoes an Ising-type transition building up true long-range order, which is induced by the anisotropic spin- orbit coupling. Based on the Bogoliubov approach, expressions for the total- and relative-phase fluctuations are derived analytically for the low temperature regime. Numerical simulations of the stochastic projected Gross- Pitaevskii equation give a good agreement with the analytical predictions.A two-dimensional spin-orbit coupled Bose gas is shown to simultaneously possess quasi and true long-range orders in the total and relative phases, respectively. The total phase undergoes a conventional Berenzinskii- Kosterlitz-Thouless transition, where an quasi long-range order is expected. Additionally, the relative phase undergoes an Ising-type transition building up true long-range order, which is induced by the anisotropic spin- orbit coupling. Based on the Bogoliubov approach, expressions for the total- and relative-phase fluctuations are derived analytically for the low temperature regime. Numerical simulations of the stochastic projected Gross- Pitaevskii equation give a good agreement with the analytical predictions.

Sep 18, 20161 citation

Phase transition in two-dimensional multicomponent Bose liquid: a new type of quasi-long-range order

I. V. Tokatly

The $ν$ -component two-dimensional (2D) Bose liquid is considered. It is shown that the finite temperature phase transition exists in this 2D continuously degenerate multicomponent system. The new type of quasi-long-range order occurs as a result of this transition. The correlation function in ordered state is a product of the power-law XY-universality class type function and the exponential function corresponding to the $SU(ν)$ invariant model. The transition temperature is calculated for the diluted system. It is found that the physical mechanism of the phase transition is changed when $ν$ exceeds the critical value $ν_c = 4$ . The experimental realization of the considered model is discussed briefly.The $ν$-component two-dimensional (2D) Bose liquid is considered. It is shown that the finite temperature phase transition exists in this 2D continuously degenerate multicomponent system. The new type of quasi-long-range order occurs as a result of this transition. The correlation function in ordered state is a product of the power-law XY-universality class type function and the exponential function corresponding to the $SU(ν)$ invariant model. The transition temperature is calculated for the diluted system. It is found that the physical mechanism of the phase transition is changed when $ν$ exceeds the critical value $ν_c = 4$. The experimental realization of the considered model is discussed briefly.

arXiv:cond-mat/9801130Jan 14, 19980 citations

Quasi-particle operators for the condensed Bose system

Wolfgang Weller

Acta Physica Academiae Scientiarum HungaricaeDec 1, 19650 citations

The

ν

-component two-dimensional (2D) Bose liquid is considered. It is shown that the finite temperature phase transition exists in this 2D continuously degenerate multicomponent system. The new type of quasi-long-range order occurs as a result of this transition. The correlation function in ordered state is a product of the power-law XY-universality class type function and the exponential function corresponding to the

SU(ν)

invariant model. The transition temperature is calculated for the diluted system. It is found that the physical mechanism of the phase transition is changed when

ν

exceeds the critical value

ν_c = 4

. The experimental realization of the considered model is discussed briefly.