GARNET CRYSTAL FOR SUBSTRATE OF MAGNETO-OPTICAL ELEMENT AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To obtain the gartnet crystal useful as a substrate for forming a Bi substd. rare earth iron garnet single crystal having a large lattice constant by selecting a garnet crystal having the specific compsn. constituted by manufacturing with a Czochralski method. SOLUTION: The garnet crystal having the compsn. expressed by the formula La8-(x+y) Ybx GayO12 [1.0<=x<=3.0; 2.5<=y<=4.5; 5.0<=(x+y)<=6.5] constituted by manufacturing with the Czochralski method is selected. The crystal is obtd. by melting a mixture obtd. by sufficiently mixing the oxides of La, Yb and Ga (e.g. Z: La2 O3 , Yb2 O3 , Ga2 O3 ) at weight ratios of La:Yb:Ga=3:p:q (1.0<=p<=3.0; 2.0<=q<=4.5) by atom ratio, then growing the crystal by the Czochralski method.