Gas-in-glass-a new Raman-gain medium: molecular hydrogen in solid-silica optical fibers

A new Raman-gain medium consisting of molecular hydrogen dissolved at high pressure in low-loss solid-silica optical fibers is described. Stimulated Raman gain at 0.88-microm wavelength was measured in a half-kilometer length of this H(2)-diffused fiber by using a krypton-laser pump and an injection-laser probe. The gain coefficient determined from these experiments at 0.88 microm is 5 x 10(-12) cm/W. The overtone absorption spectrum of high-pressure hydrogen in silica was observed.