Program

O.3 -- Oral, NCTP-41

Date: Monday, 1 August 2016

Time: 11h10 - 11h30

A study of supersolid phase in square lattice Bose Hubbard model at finite temperature using quantum Monte Carlo simulation

Oanh Nguyen, Phong H Nguyen, Long Dang

VNU-University of Engineering and Technology, 144 Xuan Thuy, Cau Giay, Hanoi, Vietnam

The behavior of supersolid phase at finite temperature has been investigated using quantum Monte Carlo - Worm Algorithm. The nearest and next nearest neighbor interaction Bose Hubbard model is chosen as a minimum model of supersolid phase in square lattice. The appearance of supersolid phase at zero temperature driven by interaction at zero temperature will be represented by the two order parameters which are superfluid density and static structure factor. QMC is able to access these different order parameters which are responsible for the different phases such as superfluid, supersolid as well as the crystal phases. It is also doable to investigate the system at finite temperature, hence the phase transition. As shown in this work, these supersolid order paramters also survive at finite temperature. The rich phase diagram has been achieved and the critical exponents falls into XY-universality class will be examined. The Kosterlitz - Thouless phase transition will also be discussed. The work aims to explain the possible experiment in optical lattice and helium absorbed on top of graphite.

Presenter: Dang Dinh Long