Growth of single crystal fibers for 1.3 μm optical amplifiers by the laser-heated pedestal growth method

We describe the use of the laser-heated pedestal growth (LHPG) technique to prepare single-crystal fibers of potential solid-state laser and optical amplifier materials. Compared with other crystal growth approaches, including Czochralski and flux growth, the LHPG approach, which has very large thermal gradients at the growth interface, has fewer dislocations, resulting in crystals with improved optical quality. We discuss the use of the LHPG technique for the growth of spinel MgAl2O4:Ni2+ crystals. Such crystals are interesting as candidate materials for a 1.3 μm optical amplifier.