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arXiv · 2310.12012

Tunable ultrabroadband hybrid THz emitter combining a spintronic THz source and a GaSe crystal

Afnan Alostaz·Oliver Gueckstock·Jungwei Tong·Jana Kredl·Chihun In·Markus Münzenberg·Tom S. Seifert
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Abstract

Linear terahertz time-domain spectroscopy (THz-TDS) is a sensitive probe for material characterization including thickness measurements of thin layers. These applications critically rely on a sufficiently large bandwidth, which is not straightforwardly available in typical THz-TDS systems. Here, we introduce a hybrid THz-emitter concept based on a spintronic THz emitter that is deposited onto a thin freestanding GaSe nonlinear crystal. By tuning the parameters of this hybrid emitter, we generate an ultrabroadband spectrum covering the full range from 1 to 40 THz without any gaps at high spectral amplitudes, resulting in ultrashort THz-pulse durations of only 32 fs. Finally, we demonstrate the straightforward tunability of the carrier-envelope phase from unipolar or bipolar THz pulses with ultrashort duration.

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Afnan Alostaz, Oliver Gueckstock, Jungwei Tong, Jana Kredl, Chihun In, Markus Münzenberg, Tom S. Seifert. 2023-10-18. Tunable ultrabroadband hybrid THz emitter combining a spintronic THz source and a GaSe crystal. https://arxiv.org/abs/2310.12012

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