Yellow diode-pumped lasing of femtosecond-laser-written Dy,Tb:LiLuF4 waveguide

TL;DR

This paper reports the first demonstration of a diode-pumped femtosecond-laser-written Dy,Tb:LiLuF4 waveguide laser emitting in the yellow spectrum, achieving high efficiency and multiple wavelength operations.

Contribution

The study introduces the fabrication of Dy,Tb:LiLuF4 waveguide lasers with femtosecond laser writing, demonstrating lasing in the yellow spectrum with high efficiency and dual-wavelength capabilities.

Findings

Maximum output power of 86 mW at 574 nm

Slope efficiency of 19% from an 80 μm waveguide

Stable lasing at 578 nm with 100 mW output

Abstract

In this article we report the fabrication of a diode-pumped Dy,Tb:LiLuF4 waveguide laser operating in the yellow region of the visible spectrum. The circular depressed-cladding waveguides have been fabricated by direct femtosecond laser writing, and showed propagation losses as low as 0.07 dB/cm. By employing these structures, we obtain a maximum output power of 86 mW at 574 nm from a 60 {\mu}m diameter waveguide, and a highest slope efficiency of 19% from a 80 {\mu}m diameter depressed cladding waveguide. In addition, we demonstrate lasing at 574 nm from a half-ring surface waveguide, with a maximum output power of 12 mW. Moreover, we also obtained dual wavelength operation at 568-574 nm, with a maximum output power of 15 mW, and stable lasing at 578 nm, with an output power of 100 mW. The latter wavelength corresponds to the main transition of the atomic clock based on the neutral ytterbium atom. To the best of the authors' knowledge, this is the first demonstration of a yellow waveguide laser based on Dy-doped materials.