Observation of extreme ultraviolet superfluorescence from helium atoms ionised and excited using soft x-ray free-electron laser pulses

ハリーズ　ジェームズ, James Harries

Published Jul 24, 2019• 0 citations

Abstract

We have studied the propagation of free-electron laser pulses at a wavelength of 24.3 nm through a dense sample of helium gas. Ionisation and resonant excitation leads to strong population of the He+ 4p state, and the resulting superfluorescence, yoked superfluorescence, and free-induction decay were observed experimentally. Numerical simulations using the Maxwell-Liouville equations were used to interpret the observations.

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