Ferromagnetism in Mn-doped GaAs layers: Effects of laser annealing

The properties of Mn-doped GaAs layers grown by laser deposition were investigated with measurements of Hall effect and magneto-optical Kerr effect (MOKE). The electrical and magnetic parameters of the layers were defined by growth temperature and quantity of sputtered Mn. It was shown that room-temperature ferromagnetism is revealed by MOKE and, after ruby laser 25 ns pulse annealing, by Hall effect measurements.     

New diluted ferromagnets based on diamond-like semiconductors GaSb,InSb, InAs,Ge, and Si,supersaturated with manganese or iron impurities during laser epitaxy

The electric, magnetic, and magneto-optical properties of thin (50–100 nm) GaSb:Mn, InSb:Mn, InAs:Mn, Ge:Mn, Ge:Fe, Si:Mn, and Si:Fe layers with a Curie point up to 500 K, obtained by laser plasma deposition in vacuum in the case of strong supersaturation of a solid solution with a 3d impurity, have been experimentally investigated.     

Elastic waves in a solid subjected to shear deformation

All-Union Scientific Research Institute of Nondestructive Testing, Kishinev. Odessa Polytechnical Institute. Translated from Prikladnaya Mekhanika, Vol. 26, No. 1, pp. 77–82, January, 1990.     

Structure of Barbituratobis(2,2'-Dipyridyl)copper(II) Heptahydrate

Russian Journal of Coordination Chemistry - The structure of the complex [Cu(Bipy)2(BA)] ? 7H2O (I), where Bipy is 2,2'-dipyridyl, and BA2– is the barbituric acid anion (H2BA), is...     

Hybrid heterostructure with a nanolayer of diluted GaIn(Mn)AsSb compound in a type II broken-gap heterojunction

Nanotechnology of obtainment of diluted magnetic semiconductors based on the GaInAsSb compounds is developed using the pulsed laser ablation deposition of Mn atoms on the surface of the epitaxial layer of a quaternary alloy obtained by liquid phase epitaxy. Fabricated heterostructures were studied using high-resolution X-ray diffraction for the Bragg and grazing diffraction geometries, and the depth profiling analysis was performed by secondary ion mass spectrometry. It was established that the nanoscale region of the Ga_0.96In_0.04As_0.11Sb_0.89 epilayer near the deposition surface of atomic Mn exhibits the presence of a quinary compound with Mn atoms in the lattice of the solid solution layer.     

Nonlinearity and hysteresis in longitudinal current transport in CoSi/GaAs alloy layers deposited from laser plasma

The electron transport properties of nanosized CoSi alloy layers deposited at a lowered temperature (350°C) from laser plasma onto single-crystalline gallium arsenide have been studied. An asymmetry of the current-voltage characteristic (CVC) in the longitudinal current transport in such layers has been found, which indicates the spin polarization of charge carriers, and a substantial (up to 18%) nonlinearity and a hysteresis (up to 4%) have been revealed both at room temperature and at 77 K for comparatively low current densities (up to 5 × 10⁴ A/cm²). In repeated cycles of CVC measurements at 77 K, irreversible changes in the properties of the layers have been observed.     

Anomalous Hall effect in highly Mn-Doped silicon films

The transport and magnetic properties of Mn _x Si_{1 ? x} films with a high (x ≈ 0.35) content of Mn produced by laser deposition at growth temperatures of 300–350°C have been studied in a temperature range of 5–300 K in magnetic fields of up to 2.5 T. The films exhibit a hole-type metallic conductivity and a relatively weak change of magnetization in a temperature range of 50–200 K. An anomalous Hall effect with an essentially hysteretic behavior from 50 K up to ≈230 K has been discovered. The properties of the films are explained by the two-phase model, in which ferromagnetic clusters containing interstitial Mn ions with a localized magnetic moment are embedded in the matrix of a weak band MnSi_{2 ? x} (x ≈ 0.3) type ferromagnet with delocalized spin density.     

Anomalous ferromagnetic resonance in manganese- and aluminum-doped germanium layers deposited from the laser plasma

Ferromagnetic resonance (FMR) with an anomalous angular dependence has been observed in the Ge:(Mn, Al)/GaAs nanolayers deposited from laser plasma at a reduced temperature of 150°C. The resonance is associated with the needle-like inclusions of a high-temperature ferromagnetic phase with the Curie temperature T _C > 293 K. Such a magnetic anisotropy is confirmed by the atomicforce and magneticforce microscopy of a side chip. A low-temperature ferromagnetic phase with normal FMR and T _C < 212 K is formed between the needle-like inclusions. This phase manifests itself in the anomalous Hall effect at 77 K and probably is a solid solution of manganese in germanium.