Phase-selective cathodoluminescence spectroscopy of Er:YAG glass-ceramics

Phase-selective excitation by a field-emission electron gun was performed for an Er3+-doped Y3Al5O12 (YAG) glass-ceramics, and the emission spectra due to the 4S3/2→4I15/2 transition of Er3+ were measured. Powder X-ray diffraction analysis revealed that a single phase of YAG was precipitated in the glass-ceramics. Field-emission scanning electron microscope (FE-SEM) images indicated that two phases existed in the glass-ceramics. There was a large difference in the intensity of cathodoluminescence (CL) between these two phases. All of the spectral peaks of the phase with higher CL intensity were attributed to the 4S3/2→4I15/2 transition of Er3+ in YAG crystal. The phase with lower CL intensity is considered to be composed of the glass phase including a small amount of YAG crystals. The CL from Er3+ in the glass phase could not be detected, implying that almost all of Er3+ ions are incorporated into YAG phase.