Fiber-tip spintronic terahertz emitters
Felix Paries, Nicolas Tiercelin, Geoffrey Lezier, Mathias Vanwolleghem, Felix Selz, Maria‐Andromachi Syskaki, Fabian Kammerbauer, G. Jakob, Martin Jourdan, Mathias Kläui, Zdeněk Kašpar, Tobias Kampfrath, Tom S. Seifert, Georg von Freymann, Daniel Molter
Abstract
Spintronic terahertz emitters promise terahertz sources with an unmatched broad frequency bandwidth that are easy to fabricate and operate, and therefore easy to scale at low cost. However, current experiments and proofs of concept rely on free-space ultrafast pump lasers and rather complex benchtop setups. This contrasts with the requirements of widespread industrial applications, where robust, compact, and safe designs are needed. To meet these requirements, we present a novel fiber-tip spintronic terahertz emitter solution that allows spintronic terahertz systems to be fully fiber-coupled. Using single-mode fiber waveguiding, the newly developed solution naturally leads to a simple and straightforward terahertz near-field imaging system with a 90%-10% knife-edge-response spatial resolution of 30 µm.