Зависимость спектра спин-волновых возбуждений магнонного кристалла от поля подмагничивания

The spectrum of spin waves (SW) of tangentially magnetized films of yttrium iron garnet (YIG) with a surface metastructure in the form of gratings of etched grooves with a period Λ close to the film thickness d (Λ~d) has been experimentally and numerically studied. It has been found that the spectrum of the signal reflected from a microstrip transducer with a width w>>d,Λ located on the YIG film contains absorption lines associated with the excitation of the SW of the surface metastructure. In the case when the magnetic field H and the transducer are oriented along the grooves, the absorption lines of the metastructure are located at frequencies f* near the short-wavelength edge of the spectrum of the surface magnetostatic (Damon-Eshbach) wave fs. It is shown that f* linearly depends on H , which can be used to develop magnetic field sensors. The results of measurements of dependences f* (H) are in qualitative agreement with the results of micromagnetic modeling.