Miniaturized optical frequency standard for next-generation portable optical clocks

Abstract

Optical frequency standards, lasers stabilized to atomic or molecular transitions, are widely used in length metrology and laser ranging, provide a backbone for optical communications and lie at the heart of next-generation optical atomic clocks. Here we demonstrate a compact, low-power optical frequency standard based on the Doppler-free, two-photon transition in rubidium-87 at 778 nm implemented on a micro-optics breadboard. The optical standard achieves a fractional frequency stability of 2.9x10${}^{-12}$/$\sqrt{\ddot{I}}„$ for averaging times $\ddot{I}„$ less than 10${}^3$ s, has a volume of $\approx$35 cm${}^3$ and operates on $\approx$450 mW of electrical power. These results demonstrate a key step towards the development of compact optical clocks and the broad dissemination of SI-traceable wavelength references.

4 pages, 4 figures