Estimations of the electron-phonon coupling parameters of the spectral lines in GaAs: Er3+ and Y3Al5O12:Yb3+

Abstract

The temperature dependences (or shifts) of spectral lines 4I13/2→4I15/2 in GaAs: Er3+ and v5→v1 in Y3Al5O12:Yb3+ crystals are studied by using an approximate processing based on a full expression. This expression contains both the static effect owing to lattice thermal expansion and the dynamic effect coming from electron-phonon interaction. The static effect is evaluated from the pressure shift of spectral line position. The studies manifest that for both the pressure and temperature shifts of a spectral line, even if one shift is zero (e.g., the zero pressure shift in GaAs: Er3+ and zero temperature shift in Y3Al5O12:Yb3+), the electron-phonon coupling parameter (charactering the dynamic effect) can be obtained from another shift. The obtained magnitudes of electron-phonon coupling parameters for 4fn ions Er3+ in GaAs and Yb3+ in Y3Al5O12 in order of magnitude are close to those of other 4fn ions in crystals and hence are reasonable.