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We demonstrate a magnetooptic spatial light modulator with one-step pattern formation of iron-garnet films on ion-milled substrates by liquid-phase epitaxy (LPE). The one-step pixel growth is acquired by the combination of a single-crystal epitaxial fill growth by LPE and an impeded film growth on a substrate whose surface has been locally damaged and milled by ion bombardment before film deposition. The interface between pixel (single-crystal expitaxial area) and pixel gap (perturbed epitaxial area) guides magnetic walls just like a groove. The fabricated prototype magnetooptic spatial light modulator (MOSLM) is switched by applying driving currents of 40 mA for the bottom conductor line and 80 mA for the top conductor line under external bias field of 20 Oe, which is over two times smaller than that of the conventional MOSLM. The novel MOSLM can provide higher resolution, simpler fabrication process, more compact systems, and lower driving current. Index Terms--Garnet films, magnetooptic effects, magnetooptic modulation.

We magnetooptically investigated how to make flat-surface pixels for a magnetooptic spatial-light modulator (MOSLM) without a physically isolated iron-garnet film. The flat-surface pixels were produced by the combinatory use of local annealing and metal stress effects. In particular, an Al layer as a mask for thermal infrared (IR) annealing was used to acquire enhanced reflectivity of the pixel area and a simpler fabrication process. In addition, ten times smaller switching bias field was acquired, compared to the physically-isolated pixel. The MOSLM with flat-surface pixels can make a compact system with higher resolution, a simpler fabrication process, and a very low driving current. Index Terms--Infrared (IR) annealing, iron-garnet film, LPE, magnetooptic spatial light modulator (MOSLM), spatial-light modulator (SLM), stress field.

A magneto-optic spatial light modulator driven by an electric field is fabricated by using the electrostrictive effect of [Pb(Zr[SUB0.52]Ti[SUB0.48])O[SUB3]] (PZT) thin film. As the stress field induced by the PZT thin film reduces the anisotropy energy of the structured garnet film, we find that the pixels can be easily switched in accordance with or without the small external bias field. When peak-to-peak 8 V at the X and Y conductors is applied with the external bias field of 40 Oe at the fabricated device, the selected pixel is switched independently. [ABSTRACT FROM AUTHOR]

We magneto-optically investigate the switching properties of the grooved pixels. The switching field of the 70%-grooved pixel achieves a factor of over two reductions more than that of the 100%-grooved pixel. The switching properties of the geometric pixel arrays for the magneto-optic spatial light modulators are very sensitive to the depth of the pixel groove, and also depend on the state of individual pixel, in additions to the state of the neighbors in two-dimensional pixel arrays. Optimally grooved pixels can allow high amounts of bismuth in the iron garnet film, and actually reduce the driving current of the magneto-optic spatial light modulator due to a low switching threshold field. [ABSTRACT FROM AUTHOR]