Compound Semiconductor Seminar - Sahil Patel
Compound Semiconductors: Electronics, Optoelectronics & Quantum Seminar
Thursday, February 5, 2026, 12:30PM
Attend in person at the Engineering Sciences Building 1001
Sahil Patel, Graduate Student Researcher, Electrical & Computer Engineering (Moody Group)
Scalable Single-Photon Sources with III-V Quantum Dots
Scalable quantum photonics demands single-photon sources that are not only “good” in the lab, but manufacturable as repeatable building blocks for large interferometric circuits, multiplexed architectures, and quantum networks. In this talk, I will introduce the key figures of merit for evaluating single-photon sources, including single-photon purity, brightness and extraction efficiency, coherence and indistinguishability, lifetime-limited clock rate, spectral stability, and for spin-photon interfaces, the spin degree of freedom in quantum dots for photonic resource state generation.
I will then provide an overview of III–V InAs/GaAs quantum dots as an all-around high-performance solid-state emitter platform and present our recent progress in growth and characterization tailored for scalability. Using an ultra-low-density growth regime, we reproducibly achieve 2e7cm−2 with a narrow emission distribution and close-to-ideal antibunching for exciton and biexciton lines, together with short radiative lifetimes.
Finally, I will motivate why site-controlled QDs are pivotal for quantum photonics. Spatial and spectral randomness remains a core roadblock to scaling. We address this with a deterministic, etch-free placement strategy that leverages III–V/oxide material properties using oxide-defined templates and CTE-mismatch-induced strain to guide adatom diffusion and reproducibly nucleate single QDs at designed locations across a wafer.
BIO: Sahil is a PhD candidate in Electrical and Computer Engineering at UC Santa Barbara, where he received his Master's degree in 2022. His main research focus is on engineering and control of deterministic single-photon sources for quantum networking applications. His work spans III–V InAs quantum dots, including diffusion-driven approaches to site-controlled QD platforms, and VdW material-based quantum emitters and color centers in hBN/WSe2 integrated with nanophotonic and acoustic devices.