An Analysis of Traveling-wave Amplification of Surface Magnetostatic Wave

Abstract

The amplification of a surface magnetostatic wave is analyzed which propagates on the contacting surface of ferrite and semiconductor layers magnetized transversely. A hydrodynamical and collision dominant model is adopted for carriers in the semiconductor. It is explained that neither diffusion effect nor surface charges induced by the Hall effect have to be considered in this case. Maxwell's equation under adequate boundary conditions is solved to give a complex characteristic equation of real ω and complex k. The following results have been obtained from the equation. 1) When the carrier density or the thickness of the semiconductor is small, the amplification factor is proportional to both of them. 2) There is an optimum value of the carrier density or the thickness to obtain the maximum amplification factor. 3) The amplification factor depends on the direction of static magnetic field.