@misc{oai:repo.qst.go.jp:00066651,
 author = {ハリーズ, ジェームズ and Harries, James},
 month = {Mar},
 note = {We report the probable observation of superfluorescence at a wavelength of 164 nm from helium ions created and excited using pulses from the EUV free-electron laser at SACLA BL1. The emission is the second step of a superfluorescence cascade from excited 4p states. To our knowledge this is the shortest wavelength at which superfluoresence has ever been demonstrated. The high intensity of the emission and the narrow angular divergence strongly support the interpretation as superfluorescence, and numerical simulations will
also be presented which support this., 日本物理学会第73回年次大会},
 title = {EUV-FEL 励起由来のヘリウムイオンからの 164 nm 超蛍光の観測},
 year = {2018}
}