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arXiv · 0705.3416

Electron Temperature Evolution in Expanding Ultracold Neutral Plasmas

P. Gupta·S. Laha·C. E. Simien·H. Gao·J. Castro·T. Pohl·T. C. Killian
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Abstract

We have used the free expansion of ultracold neutral plasmas as a time-resolved probe of electron temperature. A combination of experimental measurements of the ion expansion velocity and numerical simulations characterize the crossover from an elastic-collision regime at low initial Gamma_e, which is dominated by adiabatic cooling of the electrons, to the regime of high Gamma_e in which inelastic processes drastically heat the electrons. We identify the time scales and relative contributions of various processes, and experimentally show the importance of radiative decay and disorder-induced electron heating for the first time in ultracold neutral plasmas.

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P. Gupta, S. Laha, C. E. Simien, H. Gao, J. Castro, T. Pohl, T. C. Killian. 2007-05-23. Electron Temperature Evolution in Expanding Ultracold Neutral Plasmas. https://doi.org/10.1103/physrevlett.99.075005

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