Vacuum ultraviolet magneto-optical studies of ferromagnetic metals using synchrotron radiation

Abstract

Magneto-optical spectroscopy of ferromagnetic metals is extended beyond the quartz limit using synchrotron radiation. Real and imaginary parts of the off-diagonal elements of the conductivity tensor are obtained from transverse Kerr effect measurements and optical constants. The magneto-optical spectra for rare-earth metals along with recent vacuum ultraviolet optical data show evidence of 4f excitations, and predict a 4f optical threshold for Gd at 6.1 eV. The magneto-optical spectra of transition metal ferromagnets exhibit primary features resulting from the joint density of states. Structure in the magneto-optical spectra of Ni confirms corresponding peaks observed in recent vacuum ultraviolet optical studies, and assigns the structure to threshold minority spin transitions originating from near the Fermi level. This interpretation agrees with previous conclusions based on infrared magneto-optical studies, and supports the Stoner model description of the magnetic ground state of ferromagnetic Ni.