| 摘要 |
PROBLEM TO BE SOLVED: To manufacture an optical element using a rare earth compound in which such a state that the problems of concentration quenching, and the like, are eliminated, without wasting a material.SOLUTION: A rare earth-containing layer 105 composed of an yttrium oxide co-doped with erbium and ytterbium is formed by physical vapor deposition, e.g., sputtering, without heating a substrate, and then aggregated in a trench 104 by heating at 1000°C, for example, thus forming a rare earth core 106 composed of a crystal of an yttrium oxide co-doped with erbium and ytterbium. When being heated, an oxide of rare earth, e.g., an yttrium oxide co-doped with erbium and ytterbium, is aggregated in a recess formed in the base and crystallized. |
