Optical and magnetic spectroscopy of rare-earth-doped yttrium aluminium borate (YAl₃(BO₃)₄) single crystals

Abstract

For Ce3+, Er3+ and Yb3+ ions, electron paramagnetic resonance (EPR) spectra typical for S' = 1/2 ions are measured for YAl3(BO3)4 (YAB) single crystal. The spectra show axial symmetry indicating that all three dopants replace Y3+ at the given dopant concentration. Corresponding - and hyperfine Ã-tensors are determined. The EPR linewidth of Ce broadens with increasing temperature due to an Orbach relaxation process. Fitting the curve with an exponential, the energy difference is found to be equal to 270 ± 16 cm−1.