Chinese Physics Letters
Ground State Property of a One-Dimensional Bose—Hubbard Model Using Time-Evolving Body Decimation
Sheng-De Ouyang, Jing Liu, Shao-Hua Xiang, Kehui Song
Abstract
We study the ground state property of the one-dimensional Bose—Hubbard model using an imaginary time evolving body decimation algorithm. The single-particle density matrix is numerically calculated for a Mott insulating system and a superfluid system separately. By plotting the chemical potential versus the filling n = N/L for U/J = 20 and U/J = 0.1, we identify the Mott gap for U/J = 20 in filling n = 1. Lastly, we investigate the occupation number of the Bloch state with quasimomentum for a system deep in the Mott phase and in the superfluid phase respectively. The results indicate Bose condensation in the quasimomentum space.