We explore a new geometry allowing effective excitation of the lowest antisymmetric standing spin wave mode in ferromagnetic metallic films with symmetrical boundary conditions. The approach is based on the use of a coplanar waveguide with the ferromagnetic film, Permalloy (Py), playing the role of the signal line. In addition, we study a signal line which is a sandwich of Py inside two nonmagnetic metallic films. We find that the thickness and conductivity of the metal films can significantly alter the amount of absorption, at ferromagnetic resonance, between the symmetric and antisymmetric spin wave modes. The experimental results are supported by numerical calculations indicating the origin of the strength of the absorption.

Nearly all liquid crystal devices use a rubbed organic layer as a method of orienting the liquid crystals. This letter studies the alignment of nematic liquid crystals by rubbed and nonrubbed metallic surfaces. For rubbed metallic films, a homogeneous planar alignment of liquid crystals is found. Nonrubbed metallic surfaces align liquid crystals nonuniformly and randomly. The alignment produced by a single rubbed metallic surface extends from 10 to 50 μm and is stable in time. These results are important because they show that the organic layer may be eliminated for some applications, including tunable microwave and infrared signal processing elements.

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