Chinese Physics Letters
Modulational Instability of Trapped Two-Component Bose–Einstein Condensates*
Jian-Wen Zhou, X. X. Li, Rui Gao, Wen-Shan Qin, Hao-Hao Jiang, Taotao Li, Ju-Kui Xue
Abstract
Abstract The modulational instability of two-component Bose–Einstein condensates (BECs) under an external parabolic potential is discussed. Based on the trapped two-component Gross–Pitaevskill equations, a time-dependent dispersion relation is obtained analytically by means of the modified lens-type transformation and linear stability analysis. It is shown that a modulational unstable time scale exists for trapped two-component BECs. The modulational properties—which are determined by the wave number, external trapping parameter, intra- and inter-species atomic interactions—are modified significantly. The analytical results are confirmed by direct numerical simulation. Our results provide a criterion for judging the occurrence of instability of the trapped two-component BECs in experiment.