Observation of a Ferromagnetic-to-Paramagnetic Phase Transition on a Ferromagnetic Surface Using Spin-Polarized Photoelectron Diffraction: Gd(0001)

E. D. Tober; F. J. Palomares; R. X. Ynzunza; R. Denecke; J. Morais; Z. Wang; G. Bino; J. Liesegang; Z. Hussain; C. S. Fadley

doi:10.1103/PhysRevLett.81.2360

Observation of a Ferromagnetic-to-Paramagnetic Phase Transition on a Ferromagnetic Surface Using Spin-Polarized Photoelectron Diffraction: Gd(0001)

E. D. Tober, F. J. Palomares, R. X. Ynzunza, R. Denecke, J. Morais, Z. Wang, G. Bino, J. Liesegang, Z. Hussain, and C. S. Fadley

Phys. Rev. Lett. 81, 2360 – Published 14 September 1998

Abstract

The ferromagnetic system Gd(0001) has been studied by spin-polarized photoelectron diffraction, using the highly spin-polarized ${}^{7}S$ and ${}^{9}S$ multiplet peaks in Gd $4 s$ and $5 s$ spectra. Temperature-dependent spin asymmetries derived from the ${}^{7}S$ -to- ${}^{9}S$ peak intensity ratios exhibit pronounced changes over a range of temperatures spanning both the bulk Curie temperature $T_{cb}$ and a surface transition temperature $T_{cs}$ that is found to be $\approx 85 K$ above $T_{cb}$ . The surface transition also appears to span several atomic layers.

Received 5 December 1997

DOI:https://doi.org/10.1103/PhysRevLett.81.2360

Authors & Affiliations

E. D. Tober^1,2, F. J. Palomares^1,2,*, R. X. Ynzunza^1,2, R. Denecke^1,2, J. Morais², Z. Wang^1,2, G. Bino², J. Liesegang^2,†, Z. Hussain³, and C. S. Fadley^1,2

¹Department of Physics, University of California, Davis, California 95616
²Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
³Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720

^*Present address: Instituto de Ciencia Materiales de Madrid (ICMM-CSIC), Cantoblanco E-28049, Madrid, Spain.
^†Permanent address: Dept. of Physics, Latrobe University, Bundoora, VIC 3083, Australia.