Laser-heated miniature pedestal growth apparatus for single-crystal optical fibers

Abstract

We have designed and built a single‐crystal fiber growth apparatus. The apparatus employs novel optical, mechanical, and electronic control systems that enable the growth of high optical quality single‐crystal fibers. We have grown oriented single‐crystal fibers of four refractory oxide materials, Al₂O₃, Cr:Al₂O₃, Nd:YAG, and LiNbO₃. These materials exhibit similar growth characteristics and yield fibers of comparable quality. Fibers as small as 20 μm in diameter and as long as 20 cm have been grown. Measured optical losses at 1.06 μm for a 10‐cm‐long, 170‐μm‐diam Cr:Al₂O₃ fiber were 0.074 dB/cm.