Origin of ferromagnetism in self-assembled Ga{sub 1-x}Mn{sub x}As quantum dots grown on Si

Journal Article · Sun Dec 12 23:00:00 EST 2010 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.3526378· OSTI ID:21518209

Wang, S L; Chen, L; Meng, K K; Xu, P F; Meng, H J; Lu, J; Zhao, J H ^[1]; Yan, W S ^[2]

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1. State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083 (China)
2. National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (China)

Self-assembled Ga{sub 1-x}Mn{sub x}As magnetic semiconductor quantum dots have been grown on Si (001) substrates using droplet epitaxy by molecular-beam epitaxy. Structural characterization reveals that these dots possess a zinc-blende lattice. The Ga{sub 1-x}Mn{sub x}As quantum dots with 8% Mn content are ferromagnetically soft and slightly anisotropic at low temperature, and show the superparamagnetic behavior with a blocking temperature of 20 K in the in-plane direction. Moreover, the results of x-ray absorption near edge structure provide direct evidences for the substitutional Mn{sup 2+} ion with a half-filled d{sup 5} configuration for the Ga site, suggesting the hole-mediated ferromagnetism in zero-dimensional Ga{sub 1-x}Mn{sub x}As quantum dots.

• OSTI ID: 21518209
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 24 Vol. 97; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION
ABSORPTION SPECTROSCOPY
ANISOTROPY
ARSENIC COMPOUNDS
ARSENIDES
CHALCOGENIDES
CHANNELING
CHARGED PARTICLES
CRYSTAL GROWTH METHODS
DROPLETS
ELECTROMAGNETIC RADIATION
EPITAXY
FERROMAGNETIC MATERIALS
FERROMAGNETISM
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
INORGANIC PHOSPHORS
IONIZING RADIATIONS
IONS
LAYERS
MAGNETIC MATERIALS
MAGNETIC SEMICONDUCTORS
MAGNETISM
MANGANESE COMPOUNDS
MANGANESE IONS
MATERIALS
MOLECULAR BEAM EPITAXY
NANOSTRUCTURES
PARTICLES
PHOSPHORS
PNICTIDES
QUANTUM DOTS
RADIATIONS
SEMICONDUCTOR MATERIALS
SORPTION
SPECTROSCOPY
SUBSTRATES
SULFIDES
SULFUR COMPOUNDS
SUPERPARAMAGNETISM
TRANSITION ELEMENT COMPOUNDS
X RADIATION
X-RAY SPECTROSCOPY
ZINC COMPOUNDS
ZINC SULFIDES