Theoretical Investigations of the Sideband Effect in Mössbauer Spectra of FeBO3

Abstract A theoretical investigation of the sideband effect in Mössbauer spectra of FeBO 3 induced by radio frequency (rf) magnetic fields is presented. Because the interpretation of the sideband effect of FeBO 3 with existing theoretical models reveals no satisfactory results modifications are developed to improve the description. Especially nonlinear acoustic properties of the sample under investigation are taken into account. It can be shown that new resonances occur leading to additional sidebands at fractional integers of the applied rf frequency which have also been experimentally observed. Taking into account this feature an improved empirical description of the sideband effect of FeBO 3 is developed. This implies that nonlinear acoustic properties must be considered to obtain an appropriate description of the sideband generation in FeBO 3 .