Decoherence by a classically small influence

作者：Zhao Wen-Lei^*; Wang Jian-Zhong; Dou Fu-Quan

来源：Acta Physica Sinica, 2012, 61(24): 240302.

DOI：10.7498/aps.61.240302

• decoherence
• quantum-classical transition
• quantum chaos

Via a system of two kicked particles that are coupled in an infinite square well, we numerically show that the interaction with a particle of very small mass is able to lead to a quantum-to-classical transition on condition that the corresponding classical dynamics is almost unaffected. With the decrease of the mass of one of the particles, its effect on the classical dynamics of the other one decreases. Such an effect is even negligible if the mass of the particle is small enough. The classically chaotic dynamics of this small particle is effective for promoting the decoherence of the heavy particle. Therefore its quantum behavior exhibits the transition from the dynamical localization to the classically chaotic diffusion with the decrease of the effective Planck's constant h. Under the perturbation from the small particle, the linear entropy is rapidly saturated as time passes by. With the decrease of h, the time-averaged linear entropy exponentially increases from zero to almost unity.

• 出版日期2012
• 单位北京理工大学; 北京大学; 北京应用物理与计算数学研究所