Felix Paries
Spintronic terahertz emitters (STEs) are terahertz sources with an unmatched broad frequency bandwidth. They consist of a thin-film stack of ferromagnetic metal (FM) and normal metal (NM) layers typically produced by sputter deposition and can be driven wavelength-independently using any ultrashort-pulsed pump laser. As a result, STEs offer excellent scalability promising a seamless transition from lab to market [1 - 4].
However, the 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. It is therefore desirable to evolve from free-space laboratory setups to fully fiber-based systems.
Here, we present a novel fiber-tip spintronic terahertz emitter solution that lays the groundwork for this evolution by allowing spintronic terahertz emitters to be fully fiber-coupled [5].
During the presentation, the results of our recent research will be shown, including terahertz signals emitted by our fiber-tip STEs, and a simple near-field imaging setup with a 90%-10% knife-edge resolution of 30 µm that naturally emerges from using single-mode optical fibers.
[1] “Spintronic sources of ultrashort terahertz electromagnetic pulses”, Tom S. Seifert et al., Appl. Phys. Lett. (2021) [2] “Spintronic terahertz emitter”, Zheng Feng et al., J. Appl. Phys. (2021) [3] ”Principles of spintronic THz emitters”, Weipeng Wu et al., J. Appl. Phys. (2021) [4] “Spintronic terahertz emitters: Status and prospects from a materials perspective”, Charlotte Bull et al., APL Mater. (2021) [5] “Fiber-tip spintronic terahertz emitters”, Felix Paries et al., arXiv:2305.01365 (2023)