2025/02/11 by Matthew Storey, Freedman, Jacob M., Storey, Matthew J. +10 · 1 citation
Engineering · Physics and Astronomy · #FOS: Physical sciences #Optical Coherence Tomography Applications #Optical and Acousto-Optic Technologies #Optics (physics.optics) #Photonic and Optical Devices
paper · pdf · doi:10.48550/arxiv.2502.08012
openalex publication_date 2025/02/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Here we present an efficient, visible-light, gigahertz-frequency acousto-optic modulator fabricated on a 200 mm wafer in a volume CMOS foundry. Our device combines a piezoelectric transducer and a photonic waveguide within a single microstructure that confines both a propagating optical mode and an electrically excitable breathing-mode mechanical resonance. By tuning the device's geometry to optimize the optomechanical interaction, we achieve modulation depths exceeding 2 rad with 15 mW applied microwave power at 2.31 GHz in a 2 mm long device. This corresponds to a modulation figure of merit of Vπ⋅ L = 0.26 Vcm in a visible-light, integrated acousto-optics platform that can be straightforwardly extended to a wide range of optical wavelengths and modulation frequencies. For the important class of gigahertz-frequency modulators that can handle hundreds of milliwatts of visible-light optical power, which are critical for scalable quantum control systems, this represents a 15x decrease in Vπ and a 100x decrease in required microwave power compared to the commercial state-of-the-art and existing work in the literature.