Zhang Chuanwei, Liu Jie, Raizen Mark G, Niu Qian
Department of Physics, and Center for Nonlinear Dynamics, The University of Texas, Austin, Texas 78712-1081, USA.
Phys Rev Lett. 2004 Feb 6;92(5):054101. doi: 10.1103/PhysRevLett.92.054101. Epub 2004 Feb 3.
A periodically kicked ring of a Bose-Einstein condensate is considered as a nonlinear generalization of the quantum kicked rotor. For weak interactions between atoms, periodic motion (antiresonance) becomes quasiperiodic (quantum beating) but remains stable. There exists a critical strength of interactions beyond which quasiperiodic motion becomes chaotic, resulting in an instability of the condensate manifested by exponential growth in the number of noncondensed atoms. Similar behavior is observed for dynamically localized states (essentially quasiperiodic motions), where stability remains for weak interactions but is destroyed by strong interactions.
玻色-爱因斯坦凝聚体的周期性驱动环被视为量子驱动转子的非线性推广。对于原子间的弱相互作用，周期性运动（反共振）会变为准周期性（量子拍频）但仍保持稳定。存在一个相互作用的临界强度，超过该强度后准周期性运动会变得混沌，导致凝聚体不稳定，表现为非凝聚原子数量呈指数增长。对于动态局域态（本质上为准周期性运动）也观察到类似行为，其中弱相互作用下保持稳定，但强相互作用会破坏这种稳定性。
