Papachristou P K, Katifori E, Diakonos F K, Constantoudis V, Mavrommatis E
Department of Physics, University of Athens, GR-15771, Athens, Greece.
Phys Rev E Stat Nonlin Soft Matter Phys. 2012 Sep;86(3 Pt 2):036213. doi: 10.1103/PhysRevE.86.036213. Epub 2012 Sep 24.
We study the dynamics of the classical and quantum mechanical scattering of a wave packet from an oscillating barrier. Our main focus is on the dependence of the transmission coefficient on the initial energy of the wave packet for a wide range of oscillation frequencies. The behavior of the quantum transmission coefficient is affected by tunneling phenomena, resonances, and kinematic effects emanating from the time dependence of the potential. We show that when kinematic effects dominate (mainly in intermediate frequencies), classical mechanics provides very good approximation of quantum results. In that frequency region, the classical and quantum transmission coefficients are in optimal agreement. Moreover, the transmission threshold (i.e., the energy above which the transmission coefficient becomes larger than a specific small threshold value) is found to exhibit a minimum. We also consider the form of the transmitted wave packet and we find that for low values of the frequency the incoming classical and quantum wave packet can be split into a train of well-separated coherent pulses, a phenomenon that admits purely classical kinematic interpretation.
我们研究了波包从振荡势垒的经典和量子力学散射的动力学。我们主要关注在广泛的振荡频率范围内，透射系数对波包初始能量的依赖性。量子透射系数的行为受到隧穿现象、共振以及由势的时间依赖性产生的运动学效应的影响。我们表明，当运动学效应占主导时（主要在中间频率），经典力学能很好地近似量子结果。在该频率区域，经典和量子透射系数达到最佳吻合。此外，发现透射阈值（即透射系数大于特定小阈值的能量）呈现出最小值。我们还考虑了透射波包的形式，并且发现对于低频值，入射的经典和量子波包可以分裂成一系列分离良好的相干脉冲，这一现象可以用纯粹的经典运动学来解释。
