Structural, morphological, and magnetic characterization of In{sub 1-x}Mn{sub x}As quantum dots grown by molecular beam epitaxy

Journal Article · Wed Aug 01 00:00:00 EDT 2012 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4745904· OSTI ID:22089386

Ferri, F. A.; Marega, E. Jr. ^[1]; Coelho, L. N. ^[2]; Kunets, V. P.; Salamo, G. J. ^[3]

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1. Instituto de Fisica de Sao Carlos, Universidade de Sao Paulo, Sao Carlos 13560-970, SP (Brazil)
2. Instituto de Fisica, Universidade de Brasilia, Brasilia 70919-970, DF (Brazil)
3. Department of Physics, University of Arkansas, Fayetteville, Arkansas 72701 (United States)

In this paper, we present a method to order low temperature (LT) self-assembled ferromagnetic In{sub 1-x}Mn{sub x}As quantum dots (QDs) grown by molecular beam epitaxy (MBE). The ordered In{sub 1-x}Mn{sub x}As QDs were grown on top of a non-magnetic In{sub 0.4}Ga{sub 0.6}As/GaAs(100) QDs multi-layered structure. The modulation of the chemical potential, due to the stacking, provides a nucleation center for the LT In{sub 1-x}Mn{sub x}As QDs. For particular conditions, such as surface morphology and growth conditions, the In{sub 1-x}Mn{sub x}As QDs align along lines like chains. This work also reports the characterization of QDs grown on plain GaAs(100) substrates, as well as of the ordered structures, as function of Mn content and growth temperature. The substitutional Mn incorporation in the InAs lattice and the conditions for obtaining coherent and incoherent structures are discussed from comparison between Raman spectroscopy and x-ray analysis. Ferromagnetic behavior was observed for all structures at 2 K. We found that the magnetic moment axis changes from [110] in In{sub 1-x}Mn{sub x}As over GaAs to [1-10] for the ordered In{sub 1-x}Mn{sub x}As grown over GaAs template.

• OSTI ID: 22089386
• Journal Information: Journal of Applied Physics, Vol. 112, Issue 3; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
ARSENIC COMPOUNDS
FERROMAGNETIC MATERIALS
GALLIUM ARSENIDES
INDIUM ARSENIDES
INDIUM COMPOUNDS
MAGNETIC MOMENTS
MAGNETIC SEMICONDUCTORS
MANGANESE
MANGANESE COMPOUNDS
MODULATION
MOLECULAR BEAM EPITAXY
NUCLEATION
QUANTUM DOTS
RAMAN SPECTRA
RAMAN SPECTROSCOPY
SUBSTRATES
SURFACES
X RADIATION