初始空间有序分布下超冷等离子体的演化模拟

The simulation of ultracold neutral plasmas in initial spatial ordered distribution

超冷等离子体是一种极低温的强耦合等离子体.无序诱导加热过程是制约其达到高耦合强度的主要因素.我们使用德拜势场单体系等离子体模型的分子动力学方法模拟超冷等离子体的演化过程,研究初始空间分布对无序诱导加热过程的影响.在周期性边界条件下,我们研究了不同初始空间下超冷等离子体的演化过程,证明了有序初始空间分布能够有效提高等离子体的最终耦合强度,其结果与近期的理论计算相符合.进一步我们在演化模拟中考虑了有限体积下超冷等离子的膨胀过程,发现其在有序初始分布下会引发无序过程显著加热超冷等离子体,导致了耦合强度的逐渐降低.

The ultralcold neutral plasmas （UNPs） is a novel plasma with an extremely low temperature. Disor- dered - inducing heating is a leading limitation of coupling strength. We employed the Debye one - component - plasma model molecular dynamic to simulate the evolution of UNPs and investigate the influence of ordered initial spatial distribution to disordered - inducing heating. Under the periodic boundary, we studied the evolution of UNPs with different initial spatial distributions. It demonstrated that ordered spatial distribution is able to increase the final coupling strength of UNPs, which agree with the latest simulations. Furthermore, we considered the expansion of UNPs and found that ordered initial spatial distribution would induce the disordered - inducing heating, leading to the reduction of coupling strength.