Excited state absorption spectroscopy of glass — Experiment and simulation

We present the excited state absorption (ESA) spectroscopy of ZBLAN:Er3+ glass. The experimental spectra were measured in broad spectral range (500–1800 nm) by the CW pump-probe technique. Judd–Ofelt (JO) approach was employed to interpret the results and to simulate the ESA spectra which were successfully confronted with the experiment. We also propose a systematic approach for prediction of various types of up-conversion mechanisms such as ESA up-conversion and photon avalanche (PA). Careful investigations were made to indicate possible up-conversion excitation channels in a wide spectral range, from 400 nm up to 2 μm.