Grazing-incidence synchrotron-radiation Fe-Mssbauer spectroscopy using a nuclear Bragg monochromator and its application to the study of magnetic thin films

Mitsui, Takaya; Masuda, Ryo*; Seto, Makoto; Suharyadi, E.*; Mibu, Ko*

An energy-domain grazing-incidence Fe-Mssbauer spectroscopy(E-GIMS) with synchrotron radiation (SR) has been developed to studysurface and interface structures of thin films. A high-brilliant Fe-Mssbauer radiation, filtered from SR by a FeBO single crystal nuclear Bragg monochromator (NBM), allows us to perform the conventional Mssbauer spectroscopy (MS) for the dilute Fe in a mirror-like film in any bunch-mode operation of SR. Theoretical and experimental study of the specular reflections from isotope-enriched (Fe: 95%) and natural-abundance (Fe: 2%) iron thin films has been carried out to clarify the basic features of coherent interference between electronic and nuclear resonant scattering of Fe-Mo"ssbauer radiation in thin films. Moreover, a new surface and interface sensitive method has been developed by the combination of SR based E-GIMS and Fe-probe layer technique, which enables us to probe interfacial complex magnetic structures in thin film with atomic-scale depth resolution.