Eur. Phys. J. B 33, 47-54 (2003)
https://doi.org/10.1140/epjb/e2003-00140-5

Polar Kerr rotation of the ferromagnet EuB₆

¹ Laboratorium für Festkörperphysik, ETH Zürich, 8093 Zürich, Switzerland
² NHMFL-FSU, Tallahassee FL 32306, USA

Corresponding author: ^a degiorgi@solid.phys.ethz.ch

Received: 30 January 2003
Revised: 21 March 2003
Published online: 23 May 2003

Abstract

Magneto-optical data on EuB₆, a ferromagnet with a Curie temperature  K, are presented and discussed in detail. We have measured the polar Kerr rotation, covering a spectral range from the infrared up to the ultraviolet, as a function of temperature between 1.5 and 20 K and in external magnetic fields between 0 and 10 T. The Kerr rotation in high fields and at low temperatures is enormous. Our observations, which implicitly reflect the large magnetoresistive effects, are shown to discriminate between the spectroscopic response of localized and itinerant electronic states. Our data analysis is based on the phenomenological Lorentz-Drude model, following from the classical dispersion theory and appropriately extended to magneto-optical experiments.