Mid-infrared laser operation of Er3+-doped BaF2 and (Sr,Ba)F2 crystals

Simone Normani; Liza Basyrova; Pavel Loiko; Abdelmjid Benayad; Alain Braud; Ammar Hideur; Patrice Camy

doi:10.1364/OL.479858

Mid-infrared laser operation of Er³⁺-doped BaF₂ and (Sr,Ba)F₂ crystals

Opt Lett. 2023 Jan 15;48(2):431-434. doi: 10.1364/OL.479858.

Authors

Simone Normani, Liza Basyrova, Pavel Loiko, Abdelmjid Benayad, Alain Braud, Ammar Hideur, Patrice Camy

PMID: 36638475
DOI: 10.1364/OL.479858

Abstract

We report on the first, to our knowledge, mid-infrared laser operation of two Er³⁺-doped barium-containing fluorite-type crystals, BaF₂ and (Sr,Ba)F₂, featuring a low-phonon energy behavior. A continuous wave 4.9 at.% Er:(Sr,Ba)F₂ laser generated 519 mW at 2.79 µm with a slope efficiency of 25.0% and a laser threshold of 27 mW. The vibronic and spectroscopic properties of these crystals are determined. The phonon energy of (Sr,Ba)F₂ is as low as 267 cm^-1. The Er³⁺ ions in this crystal feature a broadband emission owing to the ⁴I_11/2 → ⁴I_13/2 transition and a long luminescence lifetime of the ⁴I_11/2 level (10.6 ms) making this compound promising for low-threshold, broadly tunable, and pulsed 2.8-µm lasers.