Design of a Cryogenic-Friendly Spintronic Terahertz Emitter Mount for Small Samples*

Spintronic terahertz emitters are thin films of metal arranged in a fashion so that when hit with short pulses of infrared light, terahertz light  pulses are emitted. I designed a mount to both emit terahertz light and hold samples fully within a cryostat, enabling us to measure the frequency dependent transmission coefficients of smaller samples using terahertz spectroscopy. By creating terahertz pulses directly behind a sample within a cryostat, as opposed to focusing the terahertz from outside, we increase the effective numerical aperture at the point of the sample. I also grew multilayer spintronic emitters using DC sputtering and electron beam deposition, improving our signal by two orders of magnitude and reducing the relative noise.