Extracting spin from an antiferromagnet at picosecond timescales

Interfaces in magnetic heterostructures are highly investigated and debated systems in the effort to create spintronic devices with novel functionalities. In this talk I will show how time-domain THz spectroscopy can be used to gain new understanding on the non-equilibrium physics of these interfaces towards the development of faster devices.

I will focus on spin-charge conversion at antiferromagnet-heavy metals interfaces. Such heterostructures have great technological potential because antiferromagnets can generate sub-picosecond spin currents which the heavy metal converts into charge signals. I will present our recent work on the optically induced picosecond spin transfer from antiferromagnets to Pt, focussing on two studies in antiferromagnetic insulators KCoF3 and KNiF3, and in antiferromagnetic metal FeRh. Via these studies, we gain a better understanding on the microscopy of spin transfer at picosecond timescales and identify key figures of merit for its efficiency.