TY - JOUR
T1 - Competition of sequential and direct paths in two-photon ionization of he
AU - Ishikawa, Kenichi L.
AU - Ma, Ri
AU - Fukuzawa, H.
AU - Motomura, K.
AU - Yamada, A.
AU - Ueda, K.
AU - Nagaya, K.
AU - Yase, S.
AU - Mizoguchi, Y.
AU - Yao, M.
AU - Rouzee, A.
AU - Hundermark, A.
AU - Vrakking, M.
AU - Johnsson, P.
AU - Nagasono, M.
AU - Togashi, T.
AU - Tono, K.
AU - Senba, Y.
AU - Ohashi, H.
AU - Yabashi, M.
AU - Ishikawa, T.
N1 - Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2012
Y1 - 2012
N2 - We study the photoelectron angular distribution (PAD) from the two-photon ionization (TPI) of He by femtosecond EUV pulses. The calculation with the time-dependent Schrödinger equation (TDSE) and the measurement at the SPring-8 EUV-FEL show reasonable agreement. The extracted relative phase δ between the s and d wave packets are distinct from that between the corresponding eigenstates, due to the competition between sequential and direct ionization paths. When the pulse is resonant with an excited level, the sequential and direct TPI compete with each other, and δ and the PAD depend on the pulse width. On the other hand, when the Ry-dberg manifold is coherently excited, δ does not vary with the pulse width.
AB - We study the photoelectron angular distribution (PAD) from the two-photon ionization (TPI) of He by femtosecond EUV pulses. The calculation with the time-dependent Schrödinger equation (TDSE) and the measurement at the SPring-8 EUV-FEL show reasonable agreement. The extracted relative phase δ between the s and d wave packets are distinct from that between the corresponding eigenstates, due to the competition between sequential and direct ionization paths. When the pulse is resonant with an excited level, the sequential and direct TPI compete with each other, and δ and the PAD depend on the pulse width. On the other hand, when the Ry-dberg manifold is coherently excited, δ does not vary with the pulse width.
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U2 - 10.1088/1742-6596/388/3/032012
DO - 10.1088/1742-6596/388/3/032012
M3 - Conference article
AN - SCOPUS:84870581443
VL - 388
JO - Journal of Physics: Conference Series
JF - Journal of Physics: Conference Series
SN - 1742-6588
IS - PART 3
M1 - 032012
T2 - 27th International Conference on Photonic, Electronic and Atomic Collisions, ICPEAC 2011
Y2 - 27 July 2011 through 2 August 2011
ER -