RUI: Structure and dynamics of cold Rydberg gases and cold plasmas

这项建议是为了继续支持科尔比学院的一项关于冷、密、里德堡气体的研究计划。在这种环境中，里德伯原子通过偶极相互作用产生强耦合，这些力对原子的运动有很大的影响。特别是，已经观察到冷里德伯原子自发地演化为等离子体，这是一个由偶极力引发的过程。里德伯态也是由冷原子的光电离产生的超冷等离子体中的三体电子离子复合形成的。有理论和实验证据表明，里德伯原子的存在可能在控制这种等离子体中的电子温度方面发挥作用。Rydberg原子间的偶极力可以导致新的分子体系的形成，这些分子体系可以通过光谱手段来识别.我们构造了一个铷磁光阱（MOT）（密度1 × 1010 cm-3，温度100 μ K）.冷里德伯原子使用脉冲激光选择性地激发。为了对原子或分子态进行高分辨光谱分析，研制了一台可调谐毫米波源。高分辨率也使人们能够“标记”一个特定的里德堡态，并以极高的精度监测这个状态的人口动态。在不久的将来，将在三个广泛相关的领域开展工作。高n态里德堡寿命的测量，超冷等离子体中的温度控制和里德堡分子的光谱学。

This proposal is to continue support for a research program on cold, dense, RydbergGases at Colby College. The Rydberg atoms in this environment are strongly coupled by the dipoleinteraction, and these forces can have a dramatic influence on the atomic motions. Inparticular, cold Rydberg atoms have been observed to spontaneously evolve to plasma, aprocess that is initiated by dipole forces. Rydberg states are also formed by three-bodyelectron-ion recombination in ultra cold plasmas that are created by photoionization ofcold atoms. There is theoretical and experimental evidence that the presence of Rydbergatoms may play a role in control of the electron temperature in such plasmas. Dipole forcesbetween Rydberg atoms can lead to the formation of novel molecular systems, which maybe identified by spectroscopic means.A rubidium magneto-optical trap (MOT) has been constructed (density 1 x 1010 cm-3, temperature 100 uK). Cold Rydberg atoms are selectively excited using a pulsed laser. In order to perform high- resolution spectroscopy of atomic or molecular states, a tunable millimeter wave source has been built. The high resolution available from this source also enables one to "tag" a particular Rydberg state, and monitor the population dynamics of this state with great precision. In the immediate future, three broadly related areas will be pursued. Measurement of Rydberg lifetimes in hiught n states, temperature control in ultra cold plasmas and the spectroscopy of Rydberg molecules .