| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a bismuth-substituted rare earth iron garnet crystal film (RIG) capable of being produced with an insertion loss of less than 0.60 dB and a high yield, and to provide an optical isolator. <P>SOLUTION: The bismuth-substituted rare earth iron garnet crystal film is grown on a non-magnetic garnet substrate indicated by chemical formula: Gd<SB POS="POST">3</SB>(ScGa)<SB POS="POST">5</SB>O<SB POS="POST">12</SB>by a liquid-phase epitaxial growth method. The crystal film is indicated by chemical formula: La<SB POS="POST">3-x-y</SB>Gd<SB POS="POST">x</SB>Bi<SB POS="POST">y</SB>Fe<SB POS="POST">5</SB>O<SB POS="POST">12</SB>(wherein 0<x<3 and 0<y<3) and is characterized in that the La, Gd, and Bi composition ratios have, in an La-Gd-Bi ternary composition diagram, a numerical range corresponding to the interior of a quadrilateral with composition points A, B, C, and D as vertices. Composition point A (La/0.15, Gd/1.66, Bi/1.19), composition point B (La/0.32, Gd/1.88, Bi/0.80), composition point C (La/0.52, Gd/1.68, Bi/0.80), and composition point D (La/0.35, Gd/1.46, Bi/1.19). <P>COPYRIGHT: (C)2012,JPO&INPIT |
