Two crystallographic sites in erbium-doped fluoride glass by frequency-resolved and site-selective spectroscopies

Erbium-doped PZG fluoride glass (lead–zinc–gallium) has been studied using site-selective spectroscopy associated to frequency-resolved spectroscopy. Possibilities of site-selective emission using frequency-resolved spectroscopy are discussed. The existence of two crystallographic sites is demonstrated and the spectroscopic properties of Er3+ in each site is analyzed. The minority site distribution peaks at high energy at 6575 cm−1, its 4I13/2 lifetime is non-exponential and lower than 5 ms and its ground state spreads over 302 cm−1. The majority site distribution peaks at 6530 cm−1, its 4I13/2 lifetime is 11 ms and its ground state spreads over 333 cm−1. The structural origin of these two sites is discussed.