Description: Vescent Technologies (Vescent) proposes to develop a compact, low-power, ruggedized, and fully automated optical frequency comb (OFC) operating in the visible/near-infrared spectrum (400-1000 nm) to enable space-deployed optical clocks and Rydberg-atom based quantum sensors. The proposed solution will simultaneously meet the challenging performance requirements and the low size, weight, and power (SWaP) required to enable several of the 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, including relativistic geodesy, autonomous spacecraft navigation, very long baseline interferometry (VLBI), and space-based gravitational wave detection. Likewise, Rydberg-atom based quantum sensors offer similarly dramatic improvements over their classical counterparts for electric-field and microwave measurements. However, all the key optical clock platforms (e.g., based on Sr and Yb atoms/ions) and Rydberg-atom based quantum sensors can only operate reliably in laboratory environments. This is largely due to their reliance on the environmentally susceptible, high-SWaP infrastructure required to frequency stabilize multiple lasers across the visible/near-infrared spectrum. As an alternative, our proposed solution leverages the OFC’s broad spectral range and precise mode spacing to perform frequency stabilization of all relevant quantum state-preparation lasers simultaneously to the OFC itself, thereby significantly reducing both SWaP and complexity of the optical clock or quantum sensor. However, there is a clear and critical gap in field-deployable, low-SWaP, OFCs operating at relevant visible wavelengths. Our proposed solution exploits rugged nonlinear micro-optic modules in telecom-style packaging to synthesize arbitrary visible wavelengths from Vescent’s existing radiation-hardened, environmentally robust OFC.

Benefits: 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.