Time-resolved photoemission combines femtosecond pump-probe techniques with angle-resolved photoelectron spectroscopy (ARPES). New opportunities for this powerful technique arise in combination with THz excitation on one hand and ultrashort XUV probe pulses on the other hand. I will present three examples and explain how THz-ARPES can be used to measure current transport in the Dirac surface state of a three-dimensional topological insulator in a contact-free fashion and with femtosecond time-resolution [1, Figure], discuss how time-resolved photoemission orbital tomography can access ultrafast electron transfer processes at metal/organic contacts [2], and finally reveal the formation of dark excitons in a two-dimensional semiconductor a few 10 fs after optical excitation [3].
[1] J. Reimann et al., Nature 562, 396 (2018).
[2] R. Wallauer et al., Science 371, 1056 (2021).
[3] R. Wallauer et al., arXiv:2012.11385 (2020).
Tuesday, May 11th, 2021, 16:15
Link:
ttps://zoom.us/j/95934563456?pwd=RW5lLzgvU2VoOXEyZHpCVUdGREg4dz09
Meeting-ID: 959 3456 3456
Kenncode: 128856
The discussion with the speaker will be held directly after the talk, the discussion will be moderated by Prof. Peter Puschnig, Karl-Franzens University Graz.
Looking forward to your participation!
program of the Physics Colloquium:
https://www.if.tugraz.at/workshops/abstracts.php?242