Room-temperature persistent spectral hole burning of Sm/sup 2+/ in silicate-based fiber

Summary form only given. Persistent spectral hole burning (PSHB) of rare-earth-doped inorganic materials has attracted much attention in view of application to high-density optical memories. In particular, it seems that the glass materials are advantageous for application in wavelength-selective optical devices, as well as the memory devices, because of their large inhomogeneous linewidth. The wavelength-selective devices are key components in the wavelength-division multiplexing system, which is important for the next-generation optical communication technology. The problem for practical application lies in the fact that PSHB of rare-earth ions in glasses is usually observed only at temperature below 20 K. However, room-temperature PSHB has been observed recently for Sm/sup 2+/-doped crystals and glasses.