Optical Spectroscopy of Low-Phonon, Holmium-Doped Barium Fluoride (BaF2) Single Crystals
Abstract
The development of new solid-state laser materials for mid-IR laser sources continues to be of significant interest for potential applications in remote sensing of biochemical agents, medicine, and IR spectroscopy. Fluorescent materials based on holmium (Ho3+)-doped crystals and glasses with narrow phonon spectra cover a wide wavelength range between approximately 1-4 micrometer. In this work, spectroscopic characterization of the IR emission properties of trivalent Ho3+-doped barium fluoride (BaF2) was explored. BaF2 is particularly attractive due to its low maximum phonon energy of approximately 330 cm-1, which leads to low nonradiative decay rates and efficient IR fluorescence. The studied Ho3+-doped BaF2 material was grown by the Bridgman technique. Using approximately 890-nm excitation, IR emissions centered at approximately 2.0, 2.85, and 3.90 micrometer were observed from Ho3+ :BaF2 corresponding to the 5I7 right arrow 5I8, 5I6 right arrow 5I7, and 5I5 right arrow 5I6 transitions of Ho3+ ions. Spectroscopic results and data modeling including Judd-Ofelt analysis, transitions cross sections, and fluorescence dynamics are discussed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2020
- Accession Number
- AD1109686
Entities
People
- E. Brown
- Jason Mckay
- Mark Dubinskii
- Zackery Fleischman
Organizations
- United States Army Research Laboratory