Analysis of Interaction between Optical Waves and Magnetostatic Surface Waves in Three-Dimensional Optical Waveguide Using Multilayered Garnet Structure
Optical-MSSW interaction has received wide interest for realization of thin film devices for optical signal processing at microwave signal frequency. In this paper, a device structure to obtain optical-MSSW interaction in a threedimensional optical waveguide using a multilayered garnet structure is proposed and analyzed. The multilayered structure enables optimization of the waveguide parameters, separately, for optical and MSSW propagation. Interaction in a threedimensional optical waveguide is promising for integration of the device with other optical integrated circuits. Optical and MSSW propagation characteristics in the multilayered device are investigated and the optical mode conversion characteristics between the Ez pq and the E x pq modes supported by the three-dimensional optical waveguide are derived. The dependence of the mode coupling coefficient on the waveguide parameters, such as the film thicknesses, waveguide width, saturation magnetization, and the MSSW power is also analyzed. It is demonstrated through a numerical example that, by proper selection of the waveguide parameters, it is possible to achieve practical device dimensions. key words: MSSW, microstrip, waveguide, garnet, mode cou-
An optical frequency shifter using magnetostatic waves
The optical frequency shift in the collinear magnetostatic wave–optical guided mode interaction has been observed by directly measuring the change in optical wavelength due to magnetostatic waves in the 2–12 GHz range. The experimental shift is found to be in good agreement with the theoretically predicted value of 0.058 A/GHz at λ0=1.319 μm.
Long Ceramic Beam Tubes for Accelerator Magnets
The ceramic beam tubes for the fast and abort kickers and the bucker and pinger magnets used at Fermilab must meet a number of exacting requirements. The tubes must be long and sufficiently straight so as not to limit magnet design. They must have wall strength capable of withstanding the atmospheric and mechanical forces encountered during construction and operation. Vacuum tight ceramic to stainless steel transitions must be of reasonable cost; they must also withstand high temperature processing and remain vacuum tight to the 10/sup -9/ Torr range. To remove the possibility of static charge buildup each tube must have a surface coating of indium oxide applied to the inner wall. This thin coating is difficult to achieve and requires the most careful attention to detail. The methods used at Fermilab to achieve these goals are presented in this paper.