Rodney D. Henry

Ferromagnetic resonance properties of LPE YIG films

This is the first report of the ferromagnetic resonance properties of thin single-crystal YIG films grown by liquid phase epitaxy techniques (LPE). The resonance linewidths of photoetched disks are close to that of bulk YIG for both parallel and perpendicular resonance without any annealing of the films. A new type of surface spin wave, localized at the air-film interface, is shown to exist in perpendicular resonance. The boundary conditions necessary for this surface spin wave to exist are produced either by SiO 2 sputtering or ion implantation.

New approaches to hard bubble suppression

Since the discovery of hard bubbles [1,2], several techniques for their suppression have been reported [3,4]. This paper describes a new double-layer method which is more versatile than previously reported suppression techniques. It is also shown that it may be possible to prevent hard bubble generation without resorting to exchange coupling of multi-layer films. This study has also produced interesting evidence that it is only the generation of hard bubbles that is suppressed, not their existence. The latter result indicates that the existing model of hard bubble suppression [5] is incomplete.

Fabrication of thin film magnetic garnet structures for intra‐cavity laser applications

Garnet compositions similar to those used for bubble domain materials have been used to fabricate ferrimagnetic nonreciprocal devices for ring laser gyro biasing at 1.152 μm. Such devices are used inside an active laser cavity, therefore precise control of the optical and physical thickness of the films is required. Two concepts of Faraday elements have been demonstrated and new material and fabrication techniques have been developed to implement them. Operating Faraday elements with 0.5 percent insertion loss have been produced.

Bubble dynamics in multilayer garnet films

The results of transient motion of bubbles in multilayer films are presented. These results are compared to present models of dynamic conversion and ballistic overshoot, followed by a discussion of the possible spin dynamics in multilayer films.