Spectroscopic investigation of dysprosium doped BaF 2 single crystals pertaining to the 3 µm mid-IR laser potential

• Published in: Optical materials express Vol. 11; no. 10; p. 3496
• Main Authors: Fleischman, Zackery D., Brown, Ei Ei, Rosen, Jenny, Dubinskii, Mark
• Format: Journal Article
• Language: English
• Published: 01.10.2021
• ISSN: 2159-3930; 2159-3930
• DOI: 10.1364/OME.438716

We present the results of a comprehensive spectroscopic investigation pertaining to laser potential evaluation of the 3-micron Dy 3+ mid-IR transition in the low-maximum phonon energy host barium fluoride (BaF 2 ). This investigation involved absorption, fluorescence, and decay time measurements, recorded for a range of temperatures. Laser-relevant parameters such as absorption and stimulated-emission cross sections, quantum-efficiencies, and radiative lifetimes were determined for room temperature (300 K) and liquid nitrogen temperature. The peak stimulated emission cross section was found to be 0.45×10 −20 cm 2 at room temperature and 1.58×10 −20 cm 2 at 77 K. The gain cross sections, predictive of laser potential, were also derived. Finally, an examination of the nature of the non-radiative decay rates as a function of temperature was performed, showing the degree to which multi-phonon relaxation and other non-radiative pathways affect the overall fluorescence behavior.