Patent Number: 6,309,557

Title: Magnetic garnet material and faraday rotator using the same

Abstract: An object is to provide a magnetic garnet material, even if a thickness of an element is made thin, in which a sufficient Faraday rotation capacity can be obtained, a magnetic field for saturation can be controlled to be less than 200 (Oe), and a magnetic compensation temperature can be controlled to be less than 0.degree. C. as well as to provide a Faraday rotator which can be made thin, suppresses a manufacturing cost and achieves a high yielding. The above object can be achieved by a magnetic garnet material known as the general chemical formula Bi.sub.x Yb.sub.y Gd.sub.z M1.sub.3-x-y-z Fe.sub.w M2.sub.u M3.sub.5-w-u O.sub.12 and the Faraday rotator using the above material. However, M1 is more than one kind of chemical elements which can replace Bi, Yb or Gd, M2 is more than one kind of non-magnetic chemical elements which can replace Fe, and M3 is more than one kind of chemical elements which can replace Fe and M2. Further, x, y, z, w and u respectively satisfies 1.0.ltoreq.x.ltoreq.1.6, 0.3.ltoreq.y.ltoreq.0.7, 0.9.ltoreq.z.ltoreq.1.6, 4.0.ltoreq.w.ltoreq.4.3 and 0.7.ltoreq.u.ltoreq.1.0.

Inventors: Ooido; Atsushi (Tokyo, JP), Yamasawa; Kazuhito (Tokyo, JP), Goto; Masanori (Tokyo, JP), Iwatsuka; Shinji (Tokyo, JP)

Assignee: TDK Corporation

International Classification: H01F 10/24 (20060101); H01F 10/10 (20060101); H01F 001/34 ()

Expiration Date: 10/30/2018