Metallic spintronic heterostructures consisting of ultrathin ferromagnetic (FM) and non-ferromagnetic (NM) layers emit THz radiation through a distinct and efficient THz generation mechanism, which arises from the conversion of spin current generated in the FM layers into transverse charge current in the NM layers [1, 2]. We have previously demonstrated that an optimized bilayer of 2-nm Fe and 3-nm Pt epitaxial grown on 500-μm MgO substrate is a remarkably versatile spintronic THz emitter, as it exhibited fairly the same THz emission efficiency at 780-nm and 1550-nm pulsed excitation wavelengths [2]. In this work, we investigated spintronic THz generation when the Fe/Pt bilayer is epitaxial grown on 500-μm Si substrate. As with the Fe/Pt on MgO, the THz emission properties of the Fe/Pt on Si were probed by standard THz time-domain emission spectroscopy using a mode-locked femtosecond (fs) fiber laser source (pulse duration: ~100-fs; repetition rate: ~100 MHz; central wavelengths: ~780 nm, ~1550 nm).

© 2019 Japan Society of Applied Physics, The Optical Society (OSA)

PDF Article


You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
Login to access OSA Member Subscription