Eur. Phys. J. D 58, 275-279 (2010)
https://doi.org/10.1140/epjd/e2010-00090-y

Relatively-long time decay of Loschmidt echo of a Bose-Einstein condensate in a double-well potential

¹ School of Mathematics and Computer Science, Guizhou Normal University, 550001, Guiyang, P.R. China
² Department of Modern Physics, University of Science and Technology of China, 230026, Hefei, P.R. China
³ Department of Physics, Nanjing University, 210093, Nanjing, P.R. China

Corresponding author: ^a wgwang@ustc.edu.cn

Received: 3 July 2009
Revised: 18 January 2010
Published online: 6 April 2010

Abstract

We study the long-time decay of quantum Loschmidt echo (LE) of a Bose-Einstein condensate (BEC) in a double-well potential. In the tunneling and self-trapping phases of the BEC, the LE has exponential and Gaussian decays, respectively, for relatively-long times. In the crossover region, the LE behaves differently from both the tunneling and the self-trapping phases. These results indicate that relatively-long time decay of the LE is suitable for characterizing the dynamical phase transition of the BEC.