Long-term optical information storage in glass with ultraviolet-light-preprocessing-induced enhancement of the signal-to-noise ratio

This Letter describes the realization of long-term optical information storage in glass using an enhanced signal-to-noise ratio (SNR). We show that the photo-oxidation of E u 2 + ions in the glass matrix induced by ultraviolet light suppresses background signals, thereby enhancing by tenfold the SNR of E u 2 + ions photoluminescence (PL) of the dots written by a femtosecond (fs) laser. Thus, smaller dots exhibiting weak PL emission can be detected. In addition, the stored information shows excellent stability under the light irradiation with the power density up to 240 W / c m 2 . Accelerated-aging experiments indicate that the stored data can retain stability for more than 115 years at room temperature. The optical storage capacity is approximately 270 G b i t c m − 3 . This technique enables long-term, high-capacity data storage in glass media.