Abstract:
Gamma-resonance studies of ultrathin magnetic fields on $^{57}$Fe nuclei in multicomponent compounds of iron with metals and a neodymium magnet of the Nd$_2$Fe$_{14}$B composition have been carried out. It is shown that ultrathin magnetic fields $H_n$ are observed on $^{57}$Fe iron nuclei in all studied compounds, the largest of which falls on $^{57}$Fe nuclei in Ni$_{45}$Fe$_{45}$B$_{10}$, which significantly exceeds the $^{57}$Fe field in a neodymium magnet, which also has the highest magnetic induction among known permanent magnets. A qualitative analysis of the mechanism of formation of ultrathin magnetic fields on iron nuclei in the studied compounds is proposed.