Dresden 2026 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

SYQF: Symposium Interacting Degrees of Freedom in Ultrathin Quantum Films

SYQF 1: Interacting Degrees of Freedom in Ultrathin Quantum Films

SYQF 1.5: Hauptvortrag

Freitag, 13. März 2026, 11:45–12:15, HSZ/AUDI

Shining light on 2D antiferromagnets — •Dmytro Afanasiev — Radboud University

Ultrafast optical control of antiferromagnetic order is a key goal in spintronics and magnonics. Resonant excitation of local orbital degrees of freedom, such as dd transitions in transition-metal ions, offers a direct route to modify magnetic exchange and anisotropy on femtosecond timescales. However, orbitally driven photomagnetism has been demonstrated in only a few materials, and the factors governing its efficiency remain unclear.

Here, we study ultrafast spin dynamics induced by resonant pumping of dd transitions in layered antiferromagnetic thiophosphates XPS3. We first establish the photomagnetic response in single magnetic-ion compounds, where local orbital excitation triggers coherent spin precession via ultrafast anisotropy modulation. We then extend this approach to binary compounds containing two distinct transition-metal ions, demonstrating that selective excitation of specific orbital resonances strongly enhances the efficiency and controllability of magnon generation.

These results identify general design principles for orbitally driven photomagnetism in collinear antiferromagnets and establish transition-metal substitution as a powerful strategy for achieving efficient ultrafast control of antiferromagnetic spin dynamics.

Keywords: light; antiferromagnets; orbitals; magnons; efficiency