Magneto-optics and motion of the magnetization in a film-waveguide optical switch

Abstract

We discuss magnetic properties of iron-garnet films and the use of these films as film-waveguide optical switches. Our experimental study involves the observation of magnetic domains, measurements of Faraday rotation constants, coercive forces and anisotropy fields, and a detailed investigation of the switching process between 0 and 300 MHz. Our theoretical study includes magneto-optics in film waveguides, and analysis of the serpentine circuit, and an extensive calculation of the motion of the magnetization. For low driving fields, the process of optical switching is the formation of periodic domains and the subsequent motion of domain walls. For higher driving fields, the process is rotation of the magnetization in unison. The switching field required for 100% modulation is several times the anisotropy field in the film, which can be as small as 0.1 Oe.

Complete magneto‐optical TE‐TM mode conversion in Cd1–xMnxTe waveguide for integrated optical isolator

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Guided Electromagnetic Waves in a Parallel-plate Gyroelectromagnetic Biaxial Chirowaveguide

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Optical isolation in Cd_1−xMn_xTe magneto-optical waveguide grown on GaAs substrate

“…However, when the magnetic field is reduced, TE-TM conversion is also reduced.Figure 2plots the maximum mode conversion ratio as a function of a magnetic field. TE-TM waveguide mode conversion ratio R induced by the Faraday effect is expressed as a function of optical propagation length L as21…”