| 摘要 |
PURPOSE:To obtain a magnetostatic wave element with a stable operation frequency even for a rapid temperature change by constituting a magnetic circuit using a permanent magnet with a specific temperature coefficient of residual magnetic flux density. CONSTITUTION:A title item consists of a magnetic garnet film 1 which is formed on a non-magnetic substrate, a coil 5, a yoke 3, and a permanent magnet 4 where a temperature coefficient of a residual magnetic flux density is -0.03--0.05(%/ deg.C) and then a magnetic circuit 2 which applies a DC magnetic field to the magnetic garnet film 1 vertically. Also, it is formed by a magnetic garnet where a temperature coefficient of an absolute value of the magnetic garnet film 1 is -1--1.5(Gauss/ deg.C). It is a liquid-phase epitaxial magnetic garnet film 1 which is suited for forming the magnetic garnet film 1 and is expressed by an expression I. The temperature coefficient of a gap magnetic field is determined only by that of a permanent magnet and a rate of temperature compensation is determined by the permanent magnet, thus enabling stable magnetic field to be generated for rapid temperature change by using the permanent magnet with a small temperature coefficient of residual magnetic flux density. |
