@misc{oai:repo.qst.go.jp:00075780,
 author = {ハリーズ, ジェームズ and Harries, James},
 month = {Jul},
 note = {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., XXXIst International Conference on Photonic, Electronic, and Atomic Collisions},
 title = {Observation of extreme ultraviolet superfluorescence from helium atoms ionised and excited using soft x-ray free-electron laser pulses},
 year = {2019}
}