  Spintronic terahertz emitters are novel, broadband and efficient sources of
terahertz radiation, which emerged at the intersection of ultrafast spintronics
and terahertz photonics. They are based on efficient spin-current generation,
spin-to-charge-current and current-to-field conversion at terahertz rates. In
this review, we address the recent developments and applications, the current
understanding of the physical processes as well as the future challenges and
perspectives of broadband spintronic terahertz emitters.
