TY - JOUR
T1 - Hard x-ray photoemission study of near-Heusler FexSi 1-x alloys
AU - Gray, A. X.
AU - Karel, J.
AU - Minár, J.
AU - Bordel, C.
AU - Ebert, H.
AU - Braun, J.
AU - Ueda, S.
AU - Yamashita, Y.
AU - Ouyang, L.
AU - Smith, David
AU - Kobayashi, K.
AU - Hellman, F.
AU - Fadley, C. S.
PY - 2011/5/9
Y1 - 2011/5/9
N2 - The structural and electronic properties of epitaxial and amorphous Fe xSi1-x alloys with x = 0.72 and 0.67 near the binary Heusler composition of x = 0.75 were determined using hard x-ray photoelectron spectroscopy (HXPS). By performing the measurements at a photon energy of 5950.3 eV, the bulk-sensitivity of the measurement is enhanced by a factor of 4-7 compared to conventional soft x-ray photoelectron spectroscopy at about 1000 keV. HXPS probes, on average, as far as 76 Å into the Fe xSi1-x samples. Via core-level spectra, it is found in the amorphous alloy that, in spite of the disordered structure that could lead to a broad distribution of chemical environments, the Si environment is mostly unique. Valence-band spectra reveal a clear distinction between the contributions of the two inequivalent Fe sites of the most highly ordered (x = 0.72, D03) epitaxial sample. The valence-band spectra are compared to results of fully relativistic coherent potential approximation calculations performed in the framework of the one-step model of photoemission, which reveal details of the atomic-orbital makeup of various features, and generally exhibit good agreement with experiment.
AB - The structural and electronic properties of epitaxial and amorphous Fe xSi1-x alloys with x = 0.72 and 0.67 near the binary Heusler composition of x = 0.75 were determined using hard x-ray photoelectron spectroscopy (HXPS). By performing the measurements at a photon energy of 5950.3 eV, the bulk-sensitivity of the measurement is enhanced by a factor of 4-7 compared to conventional soft x-ray photoelectron spectroscopy at about 1000 keV. HXPS probes, on average, as far as 76 Å into the Fe xSi1-x samples. Via core-level spectra, it is found in the amorphous alloy that, in spite of the disordered structure that could lead to a broad distribution of chemical environments, the Si environment is mostly unique. Valence-band spectra reveal a clear distinction between the contributions of the two inequivalent Fe sites of the most highly ordered (x = 0.72, D03) epitaxial sample. The valence-band spectra are compared to results of fully relativistic coherent potential approximation calculations performed in the framework of the one-step model of photoemission, which reveal details of the atomic-orbital makeup of various features, and generally exhibit good agreement with experiment.
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U2 - 10.1103/PhysRevB.83.195112
DO - 10.1103/PhysRevB.83.195112
M3 - Article
AN - SCOPUS:79961112814
SN - 1098-0121
VL - 83
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
IS - 19
M1 - 195112
ER -