Terahertz spin currents and inverse spin Hall effect in thin-film heterostructures containing complex magnetic compounds

Abstract

Terahertz emission spectroscopy of ultrathin multilayers of magnetic and heavy metals has recently attracted much interest. This method not only provides fundamental insights into photoinduced spin transport and spin-orbit interaction at highest frequencies but has also paved the way to applications such as efficient and ultrabroadband emitters of terahertz electromagnetic radiation. So far, predominantly standard ferromagnetic materials have been exploited. Here, by introducing a suitable figure of merit, we systematically compare the strength of terahertz emission from X/Pt bilayers with X being a complex ferro-, ferri- and antiferromagnetic metal, that is, dysprosium cobalt (DyCo${}_5$), gadolinium iron (Gd${}_{24}$Fe${}_{76}$), Magnetite (Fe${}_3$O${}_4$) and iron rhodium (FeRh). We find that the performance in terms of spin-current generation not only depends on the spin polarization of the magnet's conduction electrons but also on the specific interface conditions, thereby suggesting terahertz emission spectroscopy to be a highly surface-sensitive technique. In general, our results are relevant for all applications that rely on the optical generation of ultrafast spin currents in spintronic metallic multilayers.

References in corpus (12)

• Experimental observation of the spin-Hall effect in a two dimensional spin-orbit coupled semiconductor system
• Spin Seebeck insulator
• Efficient metallic spintronic emitters of ultrabroadband terahertz radiation
• Engineering ultrafast spin currents and terahertz transients by magnetic heterostructures
• Femtosecond control of electric currents at the interfaces of metallic ferromagnetic heterostructures
• Scaling behavior of the spin pumping effect in ferromagnet/platinum bilayers
• Powerful and Tunable THz Emitters Based on the Fe/Pt Magnetic Heterostructure
• Ultrabroadband single-cycle terahertz pulses with peak fields of 300 kV cm${}^{-1}$ from a metallic spintronic emitter
• Femtosecond spin current pulses generated by the non-thermal spin-dependent Seebeck effect and interacting with ferromagnets in spin valves
• Terahertz Conductivity at the Verwey Transition in Magnetite
• Correlation between magnetism and spin-dependent transport in CoFeB alloys
• Optical investigation of magneto-structural phase transition in FeRh

Cited by in corpus (18)

• Roadmap of spin-orbit torques
• Spintronic Sources of Ultrashort Terahertz Electromagnetic Pulses
• How to manipulate magnetic states of antiferromagnets
• Terahertz spectroscopy for all-optical spintronic characterization of the spin-Hall-effect metals Pt, W and Cu${}_{80}$Ir${}_{20}$
• Principles of spintronic THz emitters
• Terahertz Emission from Compensated Magnetic Heterostructures
• TMOKE as efficient tool for the magneto-optic analysis of ultra-thin magnetic films
• Modification of spintronic terahertz emitter performance through defect engineering
• Frequency-independent terahertz anomalous Hall effect in DyCo${}_5$, Co${}_{32}$Fe${}_{68}$ and Gd${}_{27}$Fe${}_{73}$ thin films from DC to 40 THz
• Simulation of Hot-Carrier Dynamics and Terahertz Emission in Laser-Excited Metallic Bilayers
• Transition of laser-induced terahertz spin currents from torque- to conduction-electron-mediated transport
• THz pulses from optically excited Fe, Pt and Ta based Spintronic Heterostructures
• Spin-voltage-driven efficient terahertz spin currents from the magnetic Weyl semimetals Co${}_2$MnGa and Co${}_2$MnAl
• Noncollinear antiferromagnetic textures driven high harmonic generation from magnetic dynamics in the absence of spin-orbit coupling
• Magnetic domain scanning imaging using phase-sensitive THz-pulse detection
• Emergent spin Hall conductivity in Tantalum-Rhenium alloys
• Direct and inverse spin-orbit torques in antiferromagnetic and ferromagnetic FeRh/W(001)
• Observation of compact ferrimagnetic skyrmions in DyCo${}_3$ film