Propagation of General Wave Packets in Some Classical and Quantum Systems
Propagation of General Wave Packets in Some Classical and Quantum Systems
复制标题
一些经典和量子系统中一般波包的传播
DOI：
10.1088/0253-6102/45/5/031
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发表时间：
2006
影响因子：
3.1
通讯作者：
Qiong
中科院分区：
文献类型：
--
作者：
Qiong
在量子力学中，波包的中心被精确地定义为概率的中心。概率中心速度描述了波包的整个运动。在经典物理学中，没有与量子力学的概率中心速度精确对应的速度，尽管在文献中至少存在八种不同的电磁波速度。我们提出了一个能心速度来描述经典物理系统中一般波包的整体运动。它是一个可测量的量，并且对于连续和离散系统都有很好的定义。对于电磁波包，它是能量传输速度的推广。本文研究了几种经典系统中的一般波包，计算了能心速度，并用色散关系和傅里叶系数表示。这些系统包括受外力作用的弦、一维的单原子链和双原子链以及一维的经典海森堡模型。在大多数情况下，能量中心的速度减少到群速度的准单色波包。因此，它似乎也是群速度的推广。简要讨论了相对论性狄拉克方程的波包。
In quantum mechanics the center of a wave packet is precisely defined as the center of probability. The center-of-probability velocity describes the entire motion of the wave packet. In classical physics there is no precise counterpart to the center-of-probability velocity of quantum mechanics, in spite of the fact that there exist in the literature at least eight different velocities for the electromagnetic wave. We propose a center-of-energy velocity to describe the entire motion of general wave packets in classical physical systems. It is a measurable quantity, and is well defined for both continuous and discrete systems. For electromagnetic wave packets it is a generalization of the velocity of energy transport. General wave packets in several classical systems are studied and the center-of-energy velocity is calculated and expressed in terms of the dispersion relation and the Fourier coefficients. These systems include string subject to an external force, monatomic chain and diatomic chain in one dimension, and classical Heisenberg model in one dimension. In most cases the center-of-energy velocity reduces to the group velocity for quasi-monochromatic wave packets. Thus it also appears to be the generalization of the group velocity. Wave packets of the relativistic Dirac equation are discussed briefly.
影响因子：
64.8
作者：
Bajcsy, M;Zibrov, AS;Lukin, MD
通讯作者：
Lukin, MD