Ultrafast phenomena and the related techniques: beyond pump-probe scheme

日時　2024年11月1日　（金）　15：00～16：00
場所　広島大学放射光科学研究所　2階　セミナー室
講師　黒田　健太
(広島大学大学院先進理工系科学研究科)

Over the past two decades, the development of femtosecond lasers has propelled ARPES technology into the time domain. Today, time-resolved ARPES (TR-ARPES) using pump-probe methods enables the study of ultrafast electron dynamics and the electronic structure in non-equilibrium states, providing a wealth of information that cannot be obtained from conventional ARPES experiments [1]. In this presentation, I will introduce ongoing TR-ARPES research from around the world and explain two novel TR-ARPES approaches (beyond conventional pump-probe method) that we aim to implement with spin-ARPES at HiSOR [2]. The first approach involves the measurement of ultrafast spin currents using a back-side-pump configuration [3], aiming to advance the field of ultrafast opt-spintronics. The second approach is lightwave ARPES, which leverages coherent electron motions during a optical cycle [4]. I hope that this presentation will offer a platform to share and discuss the necessary perspectives and techniques required for these developments.

[1] Fabio Boschini et al., Rev. Mod. Phys. 96, 015003 (2024).
[2] Takuma Iwata et al., Sci. Rep. 14, 127 (2024).
[3] Uwe Bovensiepen’s talk at HiSOR seminar (Nov, 2022).
[4] “Petahertz electronics”, Heide et al., Nature Review Physics (2024).

問合せ先　出田真一郎（放射光科学研究所）