[21a-S622-1~12] 3.6 Ultrashort-pulse and high-intensity lasers

▲ [21a-S622-1] Probing two-electron dynamics of helium in time domain via fluorescence channel

〇(P)Vinh Hoai Trinh¹, Eiji Takahashi¹, Katsumi Midorikawa¹ (1.RIKEN Center for Advanced Photonics)

Keywords:correlation,helium,attosecond

Time-resolved study of electron correlation in many-electron systems remains challenging both experimentally and theoretically. Recently, our Laser Technology Lab has demonstrated a tabletop light source generating pulses with duration of 500 as and energy as high as 1.3 microjoule [E. J. Takahashi et. al., Nat. Commun. 4, 2691 (2013)]. Such high-intensity, short-pulse light source is expected to enhance our ability to probe electron dynamics in time domain. In this presentation, we introduce our effort in theoretically realizing an attosecond pump-probe scheme applied for two-electron system of helium. In particular, we are looking at channel in which fluorescence signal may contain information on the dynamics evolution of correlated wave packet initiated by absorption of two XUV photons. We calculate the delay dependence of helium ion in the first excited state, separating 2s and 2p channels. It is shown that the signal is related to collective motions of the wave package.