Detailed study of superfluorescence at a wavelength of 469 nm from helium ionised and excited using free-electron laser pulses

ハリーズ　ジェームズ, James Harries

Published Oct 11, 2018• 0 citations

Abstract

We have studied in detail the emission of superfluorescence at a wavelength of 469 nm (4p→3s) from helium ions created and excited using free-electron laser pulses from SACLA’s BL1. In earlier work we observed superfluorescence at visible wavelengths in neutral helium [1-5]. To observe superfluorescence from helium ions we used a wavelength of 24.3 nm, resonant with the He + 1s→4p transition and sufficiently short to ionise neutral helium atoms. The density of excited He + ions created by this sequential 2-photon absorption was sufficient to allow for the development of superfluoresence.

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