Hyperfine field anisotropy in YIG with diamagnetic impurities

The 57 Fe NMR spectra of pure yttrium iron garnet, measured at 4.2 K, exhibit a well-resolved satellite structure caused by antisite defects (yttrium ions replacing iron on a sites). The analysis of the a site spectra, obtained in a magnetic field of 0.75 T applied in several directions in the (1 1 0) plane, yielded the values of the isotropic and anisotropic terms of the hyperfine field for four resolved satellite sets.