Portable Frequency Stabilized Lasers for Quantum Technologies Using Digital Techniques

Ho Kwan Chau, Christopher P. Bridges, Peter Nisbet-Jones

Abstract: Quantum atomic technologies, such as optical clocks and atom interferometers, have demonstrated their potential in laboratory settings; however, their widespread deployment for real-world applications requires significant improvement in their size, weight, power, and cost (SWaP-C). We have fabricated compact laser avionics suitable for laser cooling and spectroscopy applications. The system employs a commercial laser diode, fiber-coupled optics, current and temperature controllers, analog-to-digital converters (ADCs), and all-digital signal processing, and operates on a single 5-V power supply. Using these components, a 780-nm laser has been stabilized to the Rb D2 transition via frequency modulation (FM) spectroscopy, with a SWaP budget of 1 L, 300 g, and less than 10 W. Due to its modular design and digital reprogrammability, the low-SWaP-C system developed here can be applied to devices across the quantum technology sector.