Low noise micro- and millimeter-wave generation on chip (Invited Paper)

Recent advances in integrated photonics are enabling for significant improvements in the generation of low-noise micro- and millimeter-wave signals. This talk will provide an overview of cutting-edge approaches integrated lasers, and reference cavities that allow the chip-scale generation of ultralow noise micro- and millimeter-waves. This will include the implementation of optical frequency division (OFD), as well as Pound-Drever-Hall locking on a single chip, which enhances the stability of self-injection locked lasers over long time scales. Addressing the lack of frequency tunability in OFD photonic techniques, we introduce a hybrid opto-electronic approach that combines OFD with direct digital synthesis to produce tunable low-phase-noise microwaves across the X-band. The synthesizer architecture is fully compatible with integrated photonic implementations, paving the way for compact, high-precision and frequency agile microwave sources in chip-scale packages. Together, these advancements represent a significant leap forward in precision frequency control with low size, weight and power integrated photonics for applications in navigation, radar-based sensing and communications.