Vescent Photonics, LLC (Vescent) proposes to develop a compact, low-power, environmentally robust optical fiber frequency comb (OFC) that operates in the visible spectrum (400-800 nm) and is constructed from telecommunications (telecom) components to enable next-generation space-deployed optical atomic clocks and Rydberg-atom based quantum sensors. The proposed system will meet the challenging performance requirements for state-of-the-art quantum sensors and clocks while maintaining a low size, weight, and power (SWaP) in a configurable platform that can be adapted to the diverse needs for several of the key space-deployed applications described in Focus Area S16.08. For example, optical atomic clocks can offer instabilities as low as 4.8x10-17 in a second, opening myriad possibilities for precision sensors addressing NASA’s core interests including accurate positioning, navigation, and timing (PNT) onboard a spacecraft as well as the measurement of weak gravitational fields in near-zero gravity. Rydberg-atom based quantum sensors offer similarly dramatic improvements for electric field and microwave measurements. However, the most promising optical atomic clock platforms (e.g., Sr and Yb lattice clocks and Sr+ and Yb+ trapped ion clocks) and Rydberg-atom based sensor platforms can only operate reliably in laboratory environments, largely due to their reliance on the environmentally susceptible, high-SWaP infrastructure required to frequency stabilize multiple lasers across the visible and near-infrared spectral regions. OFCs are an ideal substitute that can significantly reduce both SWaP and complexity of the optical atomic clock or quantum sensor. However, there is a clear and critical gap in field-deployable, low-SWaP, visible OFCs. Our proposed solution exploits rugged nonlinear micro-optic modules in telecom-style packaging to synthesize arbitrary visible frequencies from Vescent’s existing radiation-hardened, environmentally robust OFC.

This proposed visible frequency comb platform addresses NASA’s research topic area S16.08 Atomic Quantum Sensors and Clocks – Critical technology gaps related to: (1) optical atomic clocks for measurements of gravitational field variations, time-variations of physical constants, detection of dark matter, etc. and (2) Rydberg atom quantum sensors for ultra-broadband, ultra-sensitive microwave receivers for earth observation sciences. The proposed technology is relevant to the following missions: DSAC, CLPS, ISS, and Artemis.

Non-NASA applications that would benefit from a low-SWaP visible frequency comb include: optical atomic clocks for navigation in GPS-denied environments, time and frequency transfer, ultra-low phase noise microwave generation for 5G-and-beyond wireless communications and radar sensing, dual comb and precision spectroscopy, and geodetic sensing for earthquake monitoring and construction projects.