Broadband serrodyne phase modulation for optical frequency standards and spectral purity transfer

We perform low phase noise, efficient serrodyne modulation for optical frequency control and spectral purity transfer between two ultrastable lasers. After characterizing serro-dyne modulation efficiency and its bandwidth, we estimate the phase noise induced by the modulation setup by devel-oping a novel, to the best of our knowledge, composite self-heterodyne interferometer. Exploiting serrodyne mod-ulation, we phase locked a 698 nm ultrastable laser to a superior ultrastable laser source at 1156 nm by means of a frequency comb as a transfer oscillator. We show that this technique is a reliable tool for ultrastable optical frequency standards. (c) 2023 Optica Publishing Group

Automated summary

This article introduces a low phase noise, efficient serrodyne modulation method for optical frequency control and spectral purity transfer between two ultrastable lasers. The phase noise induced by the modulation setup is estimated using a novel composite self-heterodyne interferometer. By exploiting serrodyne modulation, a 698 nm ultrastable laser was phase locked to a superior 1156 nm ultrastable laser source using a frequency comb as a transfer oscillator, demonstrating the reliability of this technique for ultrastable optical frequency standards.