Magnetoacoustic Excitation of Radio‐Frequency Resonances and Echoes in Magnetic Materials

摘要

Continuous spectra of resonances are observed when some ferromagnetic substances are examined with cw or spin‐echo rf spectrometers. These resonances have previously been assigned to domain‐wall motion; evidence is presented here to show rather that they are magnetically excited acoustic vibrations. An explanation of the manner in which a nonlinear magnetoacoustic interaction allows the production of echoes in an otherwise linear system is presented. A means of suppressing these resonances to facilitate the study of nuclear magnetic resonances in magnetic materials is demonstrated.