AsGa antisite defects formed during plastic deformation of GaAs are identified by electron paramagnetic resonance (EPR) measurements. From photo-EPR results it can be concluded that the two levels this double donor located near Ec −0.75 eV and Ev +0.5 eV. These values coincident with Fermi level pinning energies at Schottky barriers. The upper related to ’’main trap’’ EL2 in GaAs. Photoluminescence experiments before after thermal annealing suggest reduce band edge luminescence efficiency. A...

A new electron trap, labeled ED1, with an activation energy of 0.68 eV has been found to appear in the deep-level transient spectroscopy spectrum n-type GaAs crystals as a result their plastic deformation at 400 °C. The trap systematically investigated taking into account broadening its level. concentration was proportional dislocation density and not affected by post-deformation annealing 500 electrons captured depend logarithmically on duration time filling pulse acceptor character...

We study radiative and nonradiative recombination at individual dislocations in GaN by cathodoluminescence performed a transmission electron microscope. The are produced indentation of dislocation free single crystals have a-type Burgers vectors (b=1/3〈112̄0〉). They aligned along 〈112̄0〉 directions the basal plane. Our direct correlation between structural optical properties on microscopic scale yields two main results: (i) 60°-basal plane show 2.9 eV; (ii) screw-type act as centers. explain...

The high-spectral-resolution spectroscopic studies of the energy gap evolution, supplemented with electronic, magnetic and structural characterization, show that modification GaAs valence band caused by Mn incorporation occurs already for a very low content, much lower than required to support ferromagnetic spin - coupling in (Ga,Mn)As. Only n-type (Ga,Mn)As content below about 0.3% Mn-related extended states are visible as feature detached from valence-band edge partly occupied electrons....

The impact of bismuth incorporation into the epitaxial layer a (Ga,Mn)As dilute ferromagnetic semiconductor on its magnetic and electromagnetic properties is studied in very thin layers quaternary (Ga,Mn)(Bi,As) compound grown GaAs substrate under compressive misfit strain. An addition small atomic fraction 1% Bi atoms, substituting As atoms layer, predominantly enhances spin-orbit coupling strength valence band. presence results decrease Curie temperature distinct increase coercive fields....

Structural and optical properties of freshly created in-grown dislocations in GaN single crystal are investigated by Raman cathodoluminescence (CL) microscopy. The introduction a high density micro-indentation is accompanied the generation intrinsic point defects. A amount VGa–impurity complexes responsible for decrease free electron concentration enhanced yellow luminescence around indentation. compressive stress induced deformation revealed scattering CL. In-grown decorated with defect...

Fundamental optical properties of thin films the (Ga,Mn)As diluted ferromagnetic semiconductor with low ($1%$--$2%$) and high ($4%$--$6%$) Mn content a reference GaAs film, grown by low-temperature molecular-beam epitaxy, have been investigated photoreflectance (PR) spectroscopy. In addition, were subjected to complementary characterization means superconducting quantum interference device magnetometry, Raman spectroscopy, high-resolution x-ray diffractometry. Thorough full-line-shape...

Impact of Bi incorporation into (Ga,Mn)As layers on their electronic- and band-structures as well magnetic structural properties has been studied. Homogenous (Ga,Mn)(Bi,As) high perfection have grown by the low-temperature molecular-beam epitaxy technique. Post-growth annealing treatment results in an improvement increase hole concentration layers. The modulation photoreflectance spectroscopy are consistent with valence-band model hole-mediated ferromagnetism This material combines Ga(Bi,As)...

The impact of incorporating Bi into (Ga,Mn)As layers on their electronic, band structure, magnetic, and structural properties has been studied. low-temperature molecular beam epitaxy technique was employed to grow homogeneous (Ga,Mn)(Bi,As) with high perfection. Post-growth annealing treatment resulted in improved magnetic properties, as well an increase the hole concentration layers. Modulation photoreflectance (PR) spectroscopy confirmed modifications valence split-off experimental results...

The effect of outdiffusion Mn interstitials from (Ga,Mn)As epitaxial layers, caused by post-growth low-temperature annealing, on their electronic- and band-structure properties has been investigated modulation photoreflectance (PR) spectroscopy. annealing-induced changes in structural magnetic the layers were examined with high-resolution X-ray diffractometry superconducting quantum interference device magnetometry, respectively. They confirmed an enhancement hole concentration, which more...

Pulsed current-induced magnetization reversal is investigated in the layer of (Ga,Mn)(Bi,As) dilute ferromagnetic semiconductor (DFS) epitaxially grown under tensile misfit strain causing perpendicular magnetic anisotropy layer. The reversal, recorded through measurements anomalous Hall effect, appearing assistance a static field parallel to current, interpreted terms spin–orbit torque mechanism. Our results demonstrate that an addition small fraction heavy Bi atoms, substituting As atoms...

From experiments on the stress-induced splitting of zero-phonon line associated with optical-absorption band originating from photoexcitation EL2 center in GaAs, Kaminska et al. concluded that this has tetrahedral symmetry, which would account for its simple point-defect structure. An alternative explanation observed pattern, involves an orthorhombic ${C}_{2v}$ is discussed paper. This both recently revealed complex structure and apparent high symmetry.

Two deep electron traps induced by lattice mismatch in relaxed GaAs1−xSbx layers (x=0% to 3%) grown liquid phase epitaxy (LPE) on GaAs substrates have been revealed means of deep-level transient spectroscopy. One the traps, that shows nonstandard, logarithmic capture kinetics and whose energy level is tied valence-band edge, has related states associated with α dislocations. The other trap attributed EL2 defect possible reasons its unexpected formation LPE-grown are briefly discussed.

Electrical properties of lattice-mismatch-induced defects in GaAs/GaAsSb and GaAs/InGaAs heterojunctions have been studied by means an electron-beam-induced current (EBIC) a scanning electron microscope deep-level transient spectroscopy (DLTS). DLTS measurements, carried out with p-n junctions formed at the interfaces, revealed one trap two hole traps induced lattice mismatch. The trap, about Ec-0.68 eV, has attributed to states associated threading dislocations ternary compound. By...

Abstract Deformation‐produced paramagnetic centres have been studied in GaAs crystals uniaxially compressed at 400° using EPR technique (X band). The effect of light with photon energies from 0.4 to 1.5 eV on the populations has investigated. On basis experimental results a model is proposed which locates energy levels two E c − 1.05 and v + 0.75 eV.