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arXiv 1001.1071quant-phcond-mat.other
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量子扩散

Quantum diffusion

Roumen Tsekov

摘要:

通过耗散的Madelung流体动力学研究量子扩散。最初的波包传播弹道,然后通过正常的扩散瞬间,后来趋于渐近次扩散的法律。结果表明,表观量子扩散系数不是一个普适的物理参数,因为它取决于初始波包的准备。本文还研究了周期势场中电子的过阻尼量子扩散,在这种情况下,波包在时间上按几何规律传播。在准平衡半经典方法的框架下,研究了氢、氘和氚原子等重粒子在周期势场中的热量子扩散,得到了隧穿效应的一个简单估计.有效的热量子温度也讨论了在固体中的μ子扩散系数的温度依赖关系。

英文摘要:

Quantum diffusion is studied via dissipative Madelung hydrodynamics. Initially the wave packet spreads ballistically, than passes for an instant through normal diffusion and later tends asymptotically to a sub-diffusive law. It is shown that the apparent quantum diffusion coefficient is not a universal physical parameter since it depends on the initial wave packet preparation. The overdamped quantum diffusion of an electron in the field of a periodic potential is also investigated; in this case the wave packet spreads logarithmically in time. Thermo-quantum diffusion of heavier particles as hydrogen, deuterium and tritium atoms in periodic potentials is studied and a simple estimate of the tunneling effect is obtained in the frames of a quasi-equilibrium semiclassical approach. The effective thermo-quantum temperature is also discussed in relation to the known temperature dependence of muon diffusivity in solids.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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