Fast Spectral Hole Burning in Sm2+-Doped Al2O3–SiO2 Glasses

High-speed persistent spectral hole burning (PSHB), 30 times faster than in a similar H2 gas treated glass, has been achieved for a samarium(II)-doped alumina–silica glass upon irradiation with X-rays. Glasses of this type, enabling fast and highly efficient hole burning, are excellent candidates for binary high-density memory devices. Hole burning probably proceeds by a novel mechanism, i.e., the reaction of the X-ray irradiation-generated Sm2+ ions with oxygen ions to re-establish the original, stable trivalent oxidation state of samarium.