title: Intense 2.8 μm emission of Ho³⁺ doped PbF₂ single crystal.
abstract: A Ho³⁺-doped PbF₂ mid-IR laser crystal was successfully grown using the vertical Bridgman method. An intense 2.8 μm emission in Ho:PbF₂ crystal was observed for the first time. By analyzing the absorption and emission measurements of the Ho:PbF₂ crystal with the Judd-Ofelt theory, the intensity parameters Ω(2,4,6), exited state lifetimes, branching ratios, and emission cross-sections were calculated. It is found that the Ho:PbF₂ crystal has high fluorescence branching ratio (20.99%), large emission cross section (1.44×10⁻²⁰ cm²), long fluorescence lifetime (5.4 ms), and high quantum efficiency (88.4%) corresponding to the stimulated emission of Ho³⁺: ⁵I₆→⁵I₇ transition. The structure of Ho:PbF₂ crystal was also analyzed by the Raman spectrum, and it was found that the Ho:PbF₂ crystal possesses low phonon energy of 257 cm⁻¹. We propose that the Ho:PbF₂ crystal may be a promising material for 2.8 μm laser applications.
authors: Peixiong
authors: P
authors: Zhang
authors: Jigang
authors: J
authors: Yin
authors: Baitao
authors: B
authors: Zhang
authors: Lianhan
authors: L
authors: Zhang
authors: Jiaqi
authors: J
authors: Hong
authors: Jingliang
authors: J
authors: He
authors: Yin
authors: Y
authors: Hang
mesh_terms: D003460:Crystallization; D005459:Fluorides; D006695:Holmium; D053844:Lasers, Solid-State; D007854:Lead; D055620:Optical Phenomena; D013050:Spectrometry, Fluorescence; D013055:Spectrophotometry, Infrared
chemical_list: C077765:lead fluoride; D007854:Lead; D005459:Fluorides; D006695:Holmium