Second harmonic generation at 399 nm resonant on the $^{1}S_{0}-^{1}P_{1}$ transition of ytterbium using a periodically poled LiNbO$_{3}$ waveguide

TL;DR

This paper presents a compact, stable method for generating 399 nm light resonant with ytterbium's transition using a periodically poled LiNbO3 waveguide, enabling efficient laser cooling applications.

Contribution

The study demonstrates high-power, stable second harmonic generation at 399 nm using a waveguide, suitable for laser cooling of ytterbium, with no power degradation over 13 hours.

Findings

25 mW output at 399 nm from 380 mW fundamental

Stable operation for 13 hours without power degradation

SHG light effectively used for laser cooling of ytterbium

Abstract

We demonstrate a compact and robust method for generating a 399-nm light resonant on the $^{1}S_{0}-^{1}P_{1}$ transition in ytterbium using a single-pass periodically poled LiNbO$_{3}$ waveguide for second harmonic generation (SHG). The obtained output power at 399 nm was 25 mW when a 798-nm fundamental power of 380 mW was coupled to the waveguide. We observed no degradation of the SHG power for 13 hours with a low power of 6 mW. The obtained SHG light has been used as a seed light for injection locking, which provides sufficient power for laser cooling ytterbium.