Photoinduced Valence Changes of Samarium Ions Inside a Silica-Based Glass with Near- Infrared Femtosecond-Laser Pulses: Materials for Three-Dimensional Optical Memory

Abstract

We report photoinduced valence changes of samarium ions inside a silica-based glass using focused femtosecond-laser pulses of 800 nm wavelength. Photoluminescence spectra reveal that femtosecond-laser irradiation reduces Sm 3+ in the vicinity of the focal point of the laser beam to Sm 2+ . The mechanism of the photoinduced reduction of Sm 3+ is discussed based on optical absorption and electron spin resonance spectra.