Suresh Mallika Irene, Schwefel Harald G L, Vogt Dominik Walter
Opt Express. 2023 Sep 25;31(20):33056-33063. doi: 10.1364/OE.498406.
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 characterized to obtain a quality (Q) factor of 2.21k at ∼150 GHz and 1.41k 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. This proof-of-concept demonstration can pave the way for the implementation of a compact, tunable and efficient device which could be integrated into nonlinear photonic platforms for THz generation, manipulation and detection.
随着太赫兹（THz）光子学领域的发展，我们展示了一种单片砷化镓（GaAs）盘形回音壁模式谐振器，它有潜力作为太赫兹非线性光学中的一个组件。GaAs是一种具有显著光学非线性的材料，当晶体被加工成微盘谐振器时，其光学非线性可以增强。使用单点金刚石车削制造了一个直径4毫米的盘形谐振器，并对其进行了表征，在约150 GHz时获得了2.21k的品质（Q）因子，在约300 GHz时获得了1.41k的品质因子。我们还使用一块金属演示了太赫兹模式高达约0.3 GHz的蓝移。这种制造后的自由度对于非线性光学过程的相位匹配要求可能是有用的，比如基于太赫兹辐射光学上转换的检测。这种概念验证演示可为实现一种紧凑、可调谐且高效的器件铺平道路，该器件可集成到用于太赫兹产生、操控和检测的非线性光子平台中。
