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21	Ultracold Neutral Plasma Evolution in an External Magnetic Field Pak, Chanhyun 26 June 2023 (has links) (PDF) We study the expansion velocity and ion temperature evolution of ultracold neutral plasmas (UNPs) of calcium atoms under the influence of a uniform magnetic field that ranges up to 200 G. In the experiments, we use a magneto-optical trap (MOT) to capture the neutral atoms and laser-induced fluorescence (LIF) to take images of the plasma. We vary the magnetic field strengths and the initial electron temperatures and observe the plasma evolution in time. We compare the ion temperature evolution to the theory introduced in the paper by Pohl et. al. [Phys. Rev. A 70, 033416 (2004)]. The evolution of the gradient of expansion velocity suggests the presence of ion acoustic waves (IAWs). We speculate that our measurements showing that the ion temperature remains relatively high throughout the evolution is a biproduct of the IAW. Coulomb coupling parameter Debye screening length ultracold neutral plasma alkaline earth metals magneto-optical trap laser-induced fluorescence Zeeman shift frequency comb Nd:YAG-pumped dye laser Doppler shift Doppler broadening Voigt profile ion acoustic waves Physical Sciences and Mathematics