We have demonstrated slot vee antenna-coupled electro-optic modulators at 24 GHz. The lost vee antenna design allows for a more robust microwave signal feed into the LiNbO3 chip, where the modulator itself acts as a slab waveguide for the microwave signal. The antenna-coupled design overcomes the velocity mismatch problems inherent in LiNbO3 traveling-wave electro-optic modulators.
Lee J. Burrows,
William B. Bridges,
"Slot-vee antenna-coupled electro-optic modulator", Proc. SPIE 3463, Photonics and Radio Frequency II, (3 November 1998); doi: 10.1117/12.330399; https://doi.org/10.1117/12.330399