Ultrafast spin currents in altermagnetic RuO2 studied by terahertz emission spectroscopy

Abstract

Recent studies have shown nonrelativistic analogues to various ferromagnetic (FM) phenomena in altermagnets (AM) [1], but their ultrafast versions at THz frequencies remain unknown. In this work, we use THz emission spectroscopy to study the spin-polarization and spin-splitter effects in AM RuO2 by replacing the FM and Pt layer in spintronic THz emitters [2]. We interpret the data in terms of crystallographic orientations of RuO2.

[1] Phys. Rev. X 12, 040501 (2022)

[2] Nat. Phot. 10, 483 (2016)

Keywords

• Ultrafast
• spin
• currents
• altermagnetic
• RuO2
• studied
• terahertz
• emission
• spectroscopy