摘要
介绍一种新的量子隧穿———非线性朗道-基纳隧穿.这种隧穿一般发生在有相互作用的二能级系统中,比如光晶格中的玻色-爱因斯坦凝聚物和分子磁体.相对于传统的线性朗道-基纳隧穿,非线性朗道-基纳隧穿由排斥相互作用带来的非线性会增强隧穿的概率.特别是当非线性非常强时,系统的绝热性会遭到破坏;一个无穷小的线性驱动都会造成有限的隧穿概率.
The basic properties of the nonlinear Landau-Zener tunnelling, a new quantum tunnelling phenomenon is reviewed, which is discovered in interacting two-level systems, such as Bose-Einstein condensates in optical lattices and molecule magnets. It is found that the nonlinearity induced by the repulsive interaction can enhance the tunnelling probability compared to the usual linear Landdau-Zener tunnelling. When the nonlinearity is strong enough, the adiabaticity can break down:an infinitely small external linear force can cause finite tunnelling probability.
出处
《大学物理》
北大核心
2006年第12期1-4,共4页
College Physics
基金
中国科学院"百人计划"资助项目
国家自然科学基金资助项目(10504040)
关键词
朗道-基纳隧穿
两能级系统
绝热演化
Landau-Zener tunnelling
two-level system
adiabatic evolution