Valence band orbital polarization in III-V ferromagnetic semiconductors

DOI: 10.1103/PhysRevB.77.073304

Authors: R. P. Campion (University of Nottingham) , A. W. Rushforth (University of Nottingham) , N. R. S. Farley (University of Nottingham) , T. K. Johal (Daresbury Laboratory) , C. T. Foxon (University of Nottingham) , B. L. Gallagher (University of Nottingham) , A. Rogalev (European Synchrotron Radiation Facility) , F. Wilhelm (European Synchrotron Radiation Facility) , A. A. Freeman (School of Physics and Astronomy, University of Nottingham) , G. Van Der Laan (Diamond Light Source) , K. W. Edmonds (University of Nottingham)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Physical Review B , VOL 77 (7) , PAGES 073304-1/4

State: Published (Approved)
Published: February 2008

Abstract: The element-specific technique of x-ray magnetic circular dichroism (XMCD) is used to directly determine the magnitude and character of the valence band orbital magnetic moments in (III,Mn)As ferromagnetic semiconductors. A distinct dichroism is observed at the AsK absorption edge, yielding an As4p orbital magnetic moment of around −0.1μB per valence band hole, which is strongly influenced by strain, indicating its crucial influence on the magnetic anisotropy. The dichroism at the GaK edge is much weaker. The K edge XMCD signals for Mn and As both have positive sign, which indicates the important contribution of Mn4p states to the MnK edge spectra.

Subject Areas: Physics

Facility: ESRF