High-Power, Fiber-Laser-Based Source for Magic-Wavelength Trapping in Neutral-Atom Optical Clocks

TL;DR

This paper introduces a high-power, fiber-laser-based 810 nm source suitable for magic-wavelength trapping in neutral-atom optical clocks, demonstrating compatibility with ultracold atom trapping and potential for scaling to higher powers.

Contribution

The work presents a novel, watt-level continuous-wave laser source at 810 nm using difference-frequency generation in PPLN, optimized for ultracold atom trapping in optical clocks.

Findings

Compatible spectral and intensity noise levels for atom trapping

Potential for wavelength tuning including 813 nm for strontium clocks

Scalability towards higher wattage output

Abstract

We present a continuous-wave, 810 nm laser with watt-level powers. Our system is based on difference-frequency generation of 532 nm and 1550 nm fiber lasers in a single pass through periodically poled lithium niobate (PPLN). We measure the broadband spectral noise and residual intensity noise to be compatible with off-resonant dipole trapping of ultracold atoms. Given the large bandwidth of the fiber amplifiers, the output can be optimized for a range of wavelengths, including the strontium clock-magic wavelength of 813 nm. Furthermore, with the exploration of more appropriate nonlinear crystals, we believe there is a path toward scaling this proof-of-principle design to many watts of power, and that this approach could provide a robust, rack-mountable trapping-laser for future use in strontium-based optical clocks.