Observation of Surface-Enhanced Magnetic Order and Magnetic Surface Reconstruction on Gd(0001)

Abstract

Epitaxial Gd(0001) has been investigated with spin-polarized low-energy-electron diffraction and the magneto-optic Kerr effect. The ferromagnetic critical temperature of the surface layer is found to lie up to 22 K above the bulk Curie point, demonstrating the existence of surface-enhanced magnetic order. Furthermore, spin-resolved photoemission spectroscopy reveals that the $4f$ spins of the surface are not ferromagnetically coupled to the bulk moments.