Claddings for single crystal optical fibers and devices and methods and apparatus for making such claddings

摘要

Methods and apparatus are shown for cladding grown single crystal optical fibers. Neodymium YAG fibers are clad with a high index glass, either melted around the fiber in a trough or extruded over the fiber surface. Lithium niobate fibers are clad through an impregnation process. The lithium niobate fiber is first coated with magnesium oxide and then heated to a temperature and for a time sufficient for the magnesium oxide dopant material to diffuse into the fiber. The dopant lowers the intrinsic refractive indices of the fiber material around its circumference, creating a cladding region around the fiber core. Single crystal fibers clad by these methods and combined with suitable pumping means or with deposited electrodes provide low-loss single mode optical components useful for amplification, electro-optical effects and acousto- optical effects.