TY - JOUR
T1 - Simultaneous measurements of superradiance at multiple wavelength from helium excited states
T2 - II. Analysis
AU - Ohae, Chiaki
AU - Harries, James R.
AU - Iwayama, Hiroshi
AU - Kawaguchi, Kentarou
AU - Kuma, Susumu
AU - Miyamoto, Yuki
AU - Nagasono, Mitsuru
AU - Nakajima, Kyo
AU - Nakano, Itsuo
AU - Shigemasa, Eiji
AU - Sasao, Noboru
AU - Uetake, Satoshi
AU - Wakabayashi, Tomonari
AU - Yoshimi, Akihiro
AU - Yoshimura, Koji
AU - Yoshimura, Motohiko
N1 - Publisher Copyright:
© 2016 The Physical Society of Japan.
Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 2016
Y1 - 2016
N2 - Previous experimental studies of superradiance (SR) in multi-level systems have been explainable using the predictions of the well-known simple two-level SR model. However our recent study [K. Nakajima et al., J. Phys. Soc. Jpn. 84, 054301 (2015)] using EUV free-electron laser excitation of helium atoms, where SR was observed at wavelengths of 502, 668, and 728 nm, revealed behaviour which necessitates a full multi-level treatment of the SR development. In this paper, we report simulations of the initial excitation by the FEL pulses, and the subsequent development of multi-level SR. The results of the simulation reproduce the experimental findings, and reveal that competitive SR on two transitions with a common upper level plays an important role in the development of the system.
AB - Previous experimental studies of superradiance (SR) in multi-level systems have been explainable using the predictions of the well-known simple two-level SR model. However our recent study [K. Nakajima et al., J. Phys. Soc. Jpn. 84, 054301 (2015)] using EUV free-electron laser excitation of helium atoms, where SR was observed at wavelengths of 502, 668, and 728 nm, revealed behaviour which necessitates a full multi-level treatment of the SR development. In this paper, we report simulations of the initial excitation by the FEL pulses, and the subsequent development of multi-level SR. The results of the simulation reproduce the experimental findings, and reveal that competitive SR on two transitions with a common upper level plays an important role in the development of the system.
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U2 - 10.7566/JPSJ.85.034301
DO - 10.7566/JPSJ.85.034301
M3 - Article
AN - SCOPUS:85008890120
SN - 0031-9015
VL - 85
JO - Journal of the Physical Society of Japan
JF - Journal of the Physical Society of Japan
IS - 3
M1 - 034301
ER -