Absorption and Fluorescence Spectra of Er3+(4f11) in LaF3

Abstract

The absorption, fluorescence, and excitation spectra of Er³⁺(4f¹¹) in LaF₃ have been investigated between 3500 and 10 000 Å. Based on an energy‐level scheme consistent with all observed spectral lines, a number of states have been identified. The parameters giving the best over‐all agreement between the predicted ``free‐ion'' spectrum and the spectrum of Er³⁺ in LaF₃ are F₂=428.708 cm^‐1, F₄=67.784 cm^‐1, F₆=6.751 cm^‐1, and ζ=2389.60 cm^‐1. The average deviation for 11 of these levels is 35.3 cm^‐1. The possible use of Er³⁺ in LaF₃ for the generation of coherent green light is also discussed.