The BerLUXS-Team @ HZB and the TRR 227 kindly invite you to the following hybrid seminar (in person and via Zoom*).

Speaker: Prof. Pranaba Kishor Muduli, Indian Institute of Technology Delhi, India

Title: Tunable spintronic THz emitter using insulating antiferromagnets and quantum materials

Abstract

Spintronic terahertz emitters have emerged as compact and broadband sources of ultrafast THz radiation, where femtosecond laser excitation generates transient spin currents that are converted into charge currents by strong spin–orbit coupling. Antiferromagnets are particularly attractive for such devices because of their ultrafast spin dynamics, absence of stray fields, and intrinsic THz-frequency resonances. At the same time, magnetic quantum materials with nontrivial band topology, such as kagome ferromagnets, provide additional opportunities for efficient and tunable THz generation.

In this talk, I will focus on spintronic THz emission from epitaxial magnetic thin-film heterostructures, including insulating Fe₂O₃/Pt bilayers and the kagome ferromagnet Fe₃Sn. I will show how the crystallographic orientation of α-Fe₂O₃ strongly influences the emitted THz signal, with R-plane α-Fe₂O₃/Pt giving a large enhancement compared with other orientations. I will also discuss recent results on epitaxial Fe₃Sn-based THz emitters, where the kagome magnetic structure and strong transverse transport responses make Fe₃Sn a promising platform for spintronic THz devices.

[1] R. Agarwal et al., Phys. Rev. B 109, 224408 (2024)
[2] R. Agarwal et al., Phys. Rev. Mater. 10, 014409 (2026)

* Zoom link will be sent on request.