Acta Physica Sinica

Adiabatic Landau-Zener tunnelling in nonlinear three-level system

Guanfang Wang, Liu Bin, Fu Li-Bin, Hong Wang Zhao, (1)北京应用物理与计算数学研究所，北京 100088; (2)北京应用物理与计算数学研究所，北京 100088;兰州大学物理科学与技术学院理论物理研究所，兰州 730000; (3)兰州大学物理科学与技术学院理论物理研究所，兰州 730000;厦门大学物理系，厦门 361005

Published Jan 1, 2007• 10 citations

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Abstract

We investigate adiabatic Landau-Zener tunnelling in nonlinear three-level system. The levels and tunnelling probability are studied with respect to the nonlinearity. For weak nonlinearity, the structures of the levels are smooth and similar to their linear counterparts. However the eigenstates of the middle-level will be unstable for some system parameters, which leads to the adiabaticity to break down and the tunnelling probability chaotic. For strong nonlinearity, the structures of the levels are distorted, including double-ring-like distortion in lower-level and butterfly-like distortion in upper-level. The adiabaticity will be broken down more badly. Finally we give a possible application of the system in triple-well trapped Bose-Einstein condensates.

DOI: 10.7498/aps.56.3733

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