Spectroscopic Investigation of Dysprosium-Doped Barium Fluoride (BaF2) Single Crystals Relevant to the 3-micrometer Mid-IR Transition

In the pursuit of new mid-IR laser gain materials, dysprosium-doped barium fluoride was evaluated for its potential laser emission in the 3.0-micrometer spectral region. Comprehensive spectroscopic characterization was performed, including absorption, fluorescence, and decay-time measurements. Laser-relevant parameters such as absorption and stimulated-emission cross sections, quantum-efficiencies, and radiative lifetimes were determined for room temperature (300 K) and cryogenic temperature (77 K). The gain cross sections, which predict overall laser performance, were also calculated.