Kang Dongdong, Sun Huayang, Dai Jiayu, Chen Wenbo, Zhao Zengxiu, Hou Yong, Zeng Jiaolong, Yuan Jianmin
Department of Physics, College of Science, National University of Defense Technology, Changsha 410073, Hunan, People's Republic of China.
1] Department of Physics, College of Science, National University of Defense Technology, Changsha 410073, Hunan, People's Republic of China [2] State Key Laboratory of High Performance Computing, National University of Defense Technology, Changsha 410073, Hunan, People's Republic of China.
Sci Rep. 2014 Jun 27;4:5484. doi: 10.1038/srep05484.
Nuclear dynamics in dense hydrogen, which is determined by the key physics of large-angle scattering or many-body collisions between particles, is crucial for the dynamics of planet's evolution and hydrodynamical processes in inertial confinement confusion. Here, using improved ab initio path-integral molecular dynamics simulations, we investigated the nuclear quantum dynamics regarding transport behaviors of dense hydrogen up to the temperatures of 1 eV. With the inclusion of nuclear quantum effects (NQEs), the ionic diffusions are largely higher than the classical treatment by the magnitude from 20% to 146% as the temperature is decreased from 1 eV to 0.3 eV at 10 g/cm(3), meanwhile, electrical and thermal conductivities are significantly lowered. In particular, the ionic diffusion is found much larger than that without NQEs even when both the ionic distributions are the same at 1 eV. The significant quantum delocalization of ions introduces remarkably different scattering cross section between protons compared with classical particle treatments, which explains the large difference of transport properties induced by NQEs. The Stokes-Einstein relation, Wiedemann-Franz law, and isotope effects are re-examined, showing different behaviors in nuclear quantum dynamics.
致密氢中的核动力学由粒子间大角度散射或多体碰撞的关键物理过程决定,对于行星演化动力学以及惯性约束聚变中的流体动力学过程至关重要。在此,我们使用改进的从头算路径积分分子动力学模拟,研究了高达1电子伏特温度下致密氢输运行为的核量子动力学。随着核量子效应(NQEs)的纳入,在10克/立方厘米的密度下,当温度从1电子伏特降至0.3电子伏特时,离子扩散比经典处理方式大幅提高,幅度从20%到146%,同时,电导率和热导率显著降低。特别地,即使在1电子伏特时离子分布相同,有核量子效应时的离子扩散也比无核量子效应时大得多。离子显著的量子离域导致质子间散射截面与经典粒子处理方式相比有显著差异,这解释了核量子效应引起的输运性质的巨大差异。我们重新审视了斯托克斯 - 爱因斯坦关系、维德曼 - 弗兰兹定律和同位素效应,它们在核量子动力学中表现出不同的行为。