Modification of the secondary-electron spin polarization in Co/Cu(110) films via gaseous adsorbates

Robert M. Reeve, Shin Liang Chin, Adrian Ionescu, Crispin H W Barnes

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The effect of O and N adsorbates on the magnetic properties of ultrathin Co/Cu(110) films was investigated in situ by measuring the spin polarization of secondary electrons emitted from the surface using Mott polarimetry. The data have been fitted to a function to take into account the exponential attenuation of the signal through the layers above, yielding a room temperature paramagnetic-ferromagnetic transition thickness of dc=3.5±1.0 monolayers (ML). This evolution was compared to the equivalent evolution for cobalt films grown on O- and N-saturated surfaces. In the case of nitrogen, the onset of ferromagnetism occurs at a thickness of 4.9±0.5 ML and the saturation polarization is reduced to 65% of the value for the bare cobalt film, implying a dramatic quenching of the magnetic moment in the uppermost layer of the films. For films grown on the oxygen surface, a change in growth mode from three-dimensional to layer-by-layer growth dominates the behavior and this leads to a decrease in dc to 2.3±0.3 ML and a 38% increase in the saturation polarization value.

Original languageEnglish
Article number184431
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume84
Issue number18
DOIs
Publication statusPublished - 28 Nov 2011
Externally publishedYes

Fingerprint

Spin polarization
Adsorbates
electron spin
Electrons
polarization
Monolayers
Cobalt
cobalt
Polarization
saturation
Polarimeters
Ferromagnetism
polarimetry
Magnetic moments
ferromagnetism
Quenching
Magnetic properties
Nitrogen
magnetic moments
attenuation

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Electronic, Optical and Magnetic Materials

Cite this

Modification of the secondary-electron spin polarization in Co/Cu(110) films via gaseous adsorbates. / Reeve, Robert M.; Chin, Shin Liang; Ionescu, Adrian; Barnes, Crispin H W.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 84, No. 18, 184431, 28.11.2011.

Research output: Contribution to journalArticle

Reeve, Robert M. ; Chin, Shin Liang ; Ionescu, Adrian ; Barnes, Crispin H W. / Modification of the secondary-electron spin polarization in Co/Cu(110) films via gaseous adsorbates. In: Physical Review B - Condensed Matter and Materials Physics. 2011 ; Vol. 84, No. 18.
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