Mn Contribution to the Valence Band of Ga0.98Mn0.02Sb - A Photoemission Study

The contribution of the Mn 3d states to the valence band of Ga0.98Mn0.02Sb, an important factor determining the properties of this system, including the mechanism responsible for the magnetic characteristics, has been revealed by photoelectron spectroscopy. The resonant photoemission experiment, carried out for photon energies close to the Mn 3d -> 3p excitation, allowed us to identify the spectral feature corresponding to emission from the Mn 3d states. The scanning of the valence band along the [100] direction of the Brillouin zone, by the angle-resolved photoemission experiment, showed that these states contributed to a dispersionless structure at the binding energy of 3.6 eV (with respect to the Fermi energy). The revealed shape of the Mn 3d contribution is consistent with the supposition that the p-d exchange interaction prevails as a mechanism supporting ferromagnetism in Ga1-xMnxSb.