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arXiv · 2306.12441

Gallium arsenide whispering gallery mode resonators for terahertz photonics

Mallika Irene Suresh·Harald G. L. Schwefel·Dominik Walter Vogt
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Abstract

As the field of terahertz (THz) photonics advances, we present a monolithic gallium arsenide (GaAs) disk-shaped whispering gallery mode resonator that has potential as a component in THz nonlinear optics. GaAs is a material with significant optical nonlinearity which can be enhanced when the crystal is shaped into a microdisk resonator. A 4-mm-disk-resonator was fabricated using single-point diamond turning and was characterised to obtain a quality (Q) factor of 2.2k at ~150 GHz and 1.4k at ~300 GHz. We also demonstrated the blue-shifting of up to ~0.3 GHz of the THz modes using a block of metal. This post-fabrication degree of freedom could be useful for phase-matching requirements for nonlinear optical processes, such as detection based on optical up-conversion of THz radiation. Such a compact, tunable and efficient device could be integrated into nonlinear photonic platforms for THz generation, manipulation and detection.

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Mallika Irene Suresh, Harald G. L. Schwefel, Dominik Walter Vogt. 2023-06-20. Gallium arsenide whispering gallery mode resonators for terahertz photonics. https://arxiv.org/abs/2306.12441

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