T. Erdogan et al., VOLUME GRATINGS FOR HOLOGRAPHIC STORAGE APPLICATIONS WRITTEN IN HIGH-QUALITY GERMANOSILICATE GLASS, Applied optics, 34(29), 1995, pp. 6738-6743
Volume holographic gratings are written with ultraviolet light in high
-optical-quality, commercially available Ge-doped silica films and in
Ge-doped optical-fiber preform sections loaded with molecular hydrogen
. In the film samples, peak refractive-index changes exceeding 10(-2)
and a sensitivity (index change/absorbed energy density) of 0.4 x 10(-
7) cm(3)/J are measured. Angular multiplexing of up to 51 gratings is
demonstrated in the preform samples.