Site of Mn in Mn {delta}-doped GaAs: X-ray absorption spectroscopy

Journal Article · Sun Jan 15 04:00:00 EST 2006 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PHYSREVB.73.0· OSTI ID:20787844

D'Acapito, F; Smolentsev, G; Boscherini, F; Piccin, M; Bais, G; Rubini, S; Martelli, F; Franciosi, A ^[1]

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1. CNR-INFM-OGG, c/o ESRF, GILDA CRG, 6 Rue Jules Horowitz, F-38043 Grenoble (France)

In order to determine the local structure of Mn in {delta}-doped GaAs layers we have carried out an x-ray absorption spectroscopy experiment at the Mn-K edge in samples grown by molecular beam epitaxy with and without Be co-doping. Mn-Mn atomic correlations have not been found within {approx}5 A radius, ruling out the presence of metallic clusters or local Mn enrichment. In samples deposited at 300 deg. C, Mn substitutionally occupies the Ga site with a local expansion ({approx_equal}2%) of the first-neighbor distance with respect to GaAs; the second neighbors remain at a distance very close to that of the host lattice, indicating that the structural perturbation induced by Mn is very localized. Ab initio simulation of the x-ray absorption near edge structure spectra confirmed that Mn enters the Ga, rather than the As, site. Samples grown at 450 deg. C exhibit a reduction of the first shell coordination number, suggesting the initial phases of MnAs precipitation. In the case of Be co-doping the downward shift of the Fermi energy leads to the appearance of Mn in tetrahedral interstitial sites, of which we provide a previously unavailable local structural description.

• OSTI ID: 20787844
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Journal Name: Physical Review. B, Condensed Matter and Materials Physics Journal Issue: 3 Vol. 73; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION
ABSORPTION SPECTROSCOPY
BERYLLIUM
COMPUTERIZED SIMULATION
COORDINATION NUMBER
CORRELATIONS
DISTANCE
DOPED MATERIALS
FERMI LEVEL
GALLIUM ARSENIDES
INTERSTITIALS
LAYERS
MANGANESE
MANGANESE ARSENIDES
MOLECULAR BEAM EPITAXY
PRECIPITATION
SEMICONDUCTOR MATERIALS
X RADIATION
X-RAY SPECTROSCOPY