Excited-state absorption of Er3+-doped LiNbO3

Abstract

The excited state absorption spectra of an Er:LiNbO3 single crystal are reported and analyzed versus polarization in both visible and near infrared spectral regions between 500 and 1800 nm. These spectra are completed with excited state excitation (ESE) spectra of the bright green anti-Stokes fluorescence observed in this material. These ESE spectra are recorded more particularly around 800 and 980 nm, and the results are analyzed in view of up-conversion laser operation after diode laser pumping around these two wavelengths.