Simien, CE, Chen YC, Gupta P, Laha S, Martinez YN, Mickelson PG, Nagel SB, Killian TC.
2005.
Absorption imaging of ultracold neutral plasmas, Apr. Ieee Transactions on Plasma Science. 33:540-541.
AbstractWe report optical absorption imaging of ultracold neutral plasmas. Imaging allows direct observation of the ion density profile and expansion of the plasma. The frequency dependence of the plasma's optical depth gives the ion absorption spectrum, which is broadened by the ion motion. We use the spectral width to monitor ion equilibration in the first 250 ns after plasma formation. On a microsecond time scale, we observe the radial acceleration of ions resulting from pressure exerted by the trapped electron gas.
Killian, TC, Chen YC, Gupta P, Laha S, Martinez YN, Mickelson PG, Nagel SB, Saenz AD, Simien CE.
2005.
Absorption imaging and spectroscopy of ultracold neutral plasmas, Jan 28. Journal of Physics B-Atomic Molecular and Optical Physics. 38:S351-S362.
AbstractAbsorption imaging and spectroscopy can probe the dynamics of an ultracold neutral plasma during the first few microseconds after its creation. Quantitative analysis of the data, however, is complicated by the inhomogeneous density distribution, expansion of the plasma and possible lack of global thermal equilibrium for the ions. In this paper, we describe methods for addressing these issues. Using simple assumptions about the underlying temperature distribution and ion motion, the Doppler-broadened absorption spectrum obtained from plasma images can be related to the average temperature in the plasma.