Clustering of Mn in (Ga,Mn)As
نویسندگان
چکیده
Clustering of (Ga,Mn)As is studied with the supercell density-functional calculations using the projector augmentedwave method. We find large binding energies for a single substitutional Mn atom to existing dimers and trimers giving rise to trimer and tetramer formation. For larger clusters this binding energy drops. In all cases studied, ferromagnetic alignment is found to be energetically more favourable than the antiferromagnetic one. r 2004 Elsevier B.V. All rights reserved. PACS: 75.50.Pp; 85.75. d
منابع مشابه
FERROMAGNETISM IN (Ga,Mn)As AND (Ga,Mn)N
(Ga,Mn)As and (Ga,Mn)N are so called diluted magnetic semiconductors, i.e. semiconductor based materials made ferromagnetic by inclusion of a magnetic element—in this case Mn. This type of materials bridge over the incompatibilities in metal–semiconductor interfaces in electronics components and have an enormous potential for future spintronics applications, where both charge and spin degrees o...
متن کاملGa sublattice defects in (Ga,Mn)As: thermodynamical and kinetic trends.
We have used positron annihilation spectroscopy and infrared absorption measurements to study the Ga sublattice defects in epitaxial Ga(1-x)MnxAs with Mn content varying from 0% to 5%. We show that the Ga vacancy concentration decreases and As antisite concentration increases with increasing Mn content. This is in agreement with thermodynamical considerations for the electronic part of the form...
متن کاملExperimental Study on the Magnetomechanical Characteristics of Ni-Mn-Ga Ferromagnetic Shape Memory Alloy Single Crystals
Magnetic shape memory properties of Ni-Mn-Ga single crystals were characterized by measurement of stress-induced martensite reorientation under constant magnetic fields. Also magnetic field-induced strain as a function of the applied magnetic field under different constant compressive stress levels has been investigated. All the experiments were performed at room temperature in which the sample...
متن کاملIntrinsic hole localization mechanism in magnetic semi- conductors
– The interplay between clustering and exchange coupling in magnetic semiconductors for the prototype (Ga1−x,Mnx)As with manganese concentrations x of 1/16 and 1/32 in the interesting experimental range is investigated. For x ∼ 6%, when all possible arrangements of two atoms within a large supercell are considered, the clustering of Mn atoms at nearest-neighbour Ga sites is energetically prefer...
متن کاملMagnetic and Structural Properties of Rapidly Quenched Tetragonal Mn Ga Nanostructures
Nanostructured Mn Ga ribbons with and 1.1 were prepared using arc-melting, melt-spinning and annealing. As-spun samples crystallized into hexagonal and cubic Heusler crystal structures based on the concentration of Mn in Mn Ga. Upon vacuum-annealing the samples at 450 C for about 50 hours, both the hexagonal and cubic structures transformed into a tetragonal structure. High-temperature x-ray di...
متن کامل