| 摘要 |
PURPOSE:To provide an optical isolator with which required operation functions are obtd. without applying a bias magnetic field thereto by consisting a Faraday rotating element of a Bi-contg. rare earth iron magnetic garnet which has hard magnetism in the optical axis direction, and in which part of the iron is substd. with a nonmagnetic element and of which 4piMs (Ms is saturation magnetization) is selected at <=100 gauss. CONSTITUTION:The Faraday rotating element is constituted by forming the thin film of the Bi-contg. rare earth iron magnetic garnet which has hard magnetism in the optical axis direction and in which part of the iron thereof is substd. with the nonmagnetic element Ga or (and) Al, Ge (group IIIA), etc., and of which 4piMs (Ms is the saturation magnetization) is set to <=100 gauss (G) onto a transparent substrate consisting of, for example, SGG (substrated gallium garnet) substrate by liquid phase epitaxy (LPE). The optical isolator having various kinds of the constitution is constituted by such Faraday rotating element and magnets are excluded from such constitution.
|
