Maximizing the Electromagnetic Efficiency of Spintronic Terahertz Emitters

• DOI: 10.1002/adpr.202400064
• Publication Date: 2024-09-04T12:11:02Z
• Authors: Pierre Koleják; Geoffrey Lezier; Daniel Vala; Baptiste Mathmann; Lukáš Halagačka; Zuzana Gelnárová; Yannick Dusch; Jean‐François Lampin; Nicolas Tiercelin; Kamil Postava; Mathias Vanwolleghem
• Keywords: Terahertz gap

Optically pumped spintronic terahertz emitters (STEs) have, in less than a decade, strongly impacted (THz) source technology, by the combination of their Fourier‐limited ultrafast response, phononless emission spectrum and wavelength‐independent operation. However, intrinsic strength inverse spin Hall effect governing these devices introduces challenge: optical‐to‐terahertz conversion efficiency is considerably lower traditional sources. It therefore primordial to maximize at least electromagnetic independently dynamics play. Using rigorous time‐domain treatment generation extraction processes, an optimized design presented experimentally confirmed. With respect strongest reported THz it achieves 250% enhancement emitted field 8 dB increase power. This experimental achievement brings STE close symbolic barrier mW levels. The strategy generically applicable any kind spin‐to‐charge (S2C) system. On broader level, our work highlights how handling purely aspects can uncover overlooked operation lead substantial improvements.