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Collinear interactions of guided light with dipole-exchange spin waves in a 4.66-μm-thick Lu2.14Bi0.86Fe4.94Mg0.06O12 single crystal film has been experimentally investigated. For all four regimes of interaction TM5→TE5, TM6→TE6, TM7→TE7, TM8→TE8 diffraction peaks had a complex ‘‘fine structure’’ indicating the splitting of the spectrum of the spin waves. Frequencies of these peaks are in good agreement with the theoretical predictions based on the numerical estimations of the strong ‘‘hybridization’’ of a magnetostatic mode with seventeen spin wave resonance modes. The analysis of the amplitudes of the diffraction peaks corresponding to different hybrid spin wave modes has shown the presence of asymmetry of the pinning conditions on the surfaces of the film.

This paper reports the maximum diffraction efficiency per unit microwave power achieved so far in experiments on the interaction of optical waveguide modes with magnetostatic waves (MSW) in ferrimagnetic films. To obtain high efficiency of the interaction a film of Lu2 .14Bi0.86Fe4.94Mg0.06O12 grown on a gadolinium gallium garnet substrate, and collinear propagation of the surface MSW and guided light were used. Measurements of the spectrum of optical modes in the film have shown extremely high values of the birefringence between a TE and a TM mode, induced by the mismatch of the lattice parameters of the film and the substrate (Δnbi = 4.5 × 10−3). A He-Ne laser (λ=1.152 μm) was used as the source of optical radiation. The measurements of the efficiency of the interaction were carried out for two geometries: (i) parallel propagation of the light and MSW, and (ii) antiparallel propagation of the light and MSW. As predicted by theory, the efficiency of the parallel interaction was higher than that of the antiparallel interaction. The efficiency for the case of the parallel interaction was of the order of 0.8% per 1 mW of the MSW microwave power.

The optimal combination of seed sprouting and extrusion processes reduces the energy, economic and labor costs of germination and decreases the loss of sprouted seed. To obtain sprouted seed, various pre-treatment methods were evaluated before the extrusion process. It was found that the optimal pre-treatment of seeds before sprouting is treatment with microwave radiation of 1400 W/dm3 for 20 s or 3% hydrogen peroxide for 10 min. When using such treatment methods, not only microflora suppression but also activation of the feed seed sprouting process are provided. The first sprouts appear in 12 hours. In 60 hours, the amount of sprouted seeds reaches 70-90 %. The length of sprouts at this stage of germination is optimal for further processing and is from 5 to 25 mm.

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