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 (STFC 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 (University of Nottingham) , G. Van Der Laan (STFC Daresbury Laboratory; 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 As K absorption edge, yielding an As 4 p orbital magnetic moment of around − 0.1 μ B per valence band hole, which is strongly influenced by strain, indicating its crucial influence on the magnetic anisotropy. The dichroism at the Ga K edge is much weaker. The K edge XMCD signals for Mn and As both have positive sign, which indicates the important contribution of Mn 4 p states to the Mn K edge spectra.

Diamond Keywords: Ferromagnetism; Semiconductors; Spintronics

Subject Areas: Physics, Materials

Facility: ID12 at ESRF

Added On: 19/08/2009 23:07

Discipline Tags:

Quantum Materials Physics Electronics Magnetism Materials Science

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