Search

A technology has been developed and an optimal solution has been found for obtaining p0-n0 junctions based on lightly doped GaAs layers, with high values of electrical parameters and specified thicknesses of the base layers for creating ultra-high-speed high-voltage pulsed three-electrode switches with a photoninjection mechanism for the transfer of no ne quorum charge carriers. The dependence of the switching stability relative to the control pulse of the created high-voltage photonic-injection switches in a wide current and frequency mode of their operation, its sensitivity to various external and internal influences of these parameters has been studied. Those on the thickness of the p0-layer, on the transfer coefficient &945;, on the breakdown voltage Utrial, high-voltage p0-n0 transition, on the thickness of the solution-melt, on the temperature of the onset of crystallization, as well as the dependence of the transfer coefficient on the thickness of the p0-layer. [ABSTRACT FROM AUTHOR]

In this work, a new model has been developed for calculating the effect of a quantizing magnetic field on the temperature dependence of the two-dimensional combined density of states in direct-gap heterostructures with quantum wells. The temperature dependence of the oscillations of the two-dimensional combined density of states of the quantum well is explained by the thermal smearing of the Gaussian distribution function in a strong magnetic field. Based on the proposed new models, the Landau levels of charge carriers in a direct-gap quantum well are determined in a wide temperature range. The experimental results were interpreted using the oscillations of the combined density of states of the quantum well in a quantizing magnetic field. [ABSTRACT FROM AUTHOR]

We report on the magnetic properties of epitaxial La0.7Ba0.3MnO3 and La0.7Sr0.3MnO3 films on Si (100) and Si (111) substrates using SrTiO3 template layer, which demonstrate magnetic and electrical properties at and above room temperature. The magnetization data show magnetic transition and magnetic hysteresis at and above room room temperature. The films show well-defined magnetic domains. The ferromagnetic resonance studies show anisotropic effects related to ferromagnetic properties of films. The smaller grain size of about 20 nm in manganite films on SrTiO3/Si may be one of the reasons to minimize the strain effect through strain relaxation at the interface between SrTiO3 and manganites through the formation of three-dimensonal islands. [ABSTRACT FROM AUTHOR]

We report the growth and magnetic characterizations of La0.7Ba0.3MnO3 and La0.7Sr0.3MnO3 films on SrTiO3-buffered Si (100) and Si (111) substrates by pulsed-laser deposition. The structural studies show the epitaxial nature of the films. The microscopic studies show that the films consist of nanocrystalline particles. All films display sharp magnetic and electrical transitions associated with the colossal magnetoresistance behavior at and above room temperature, illustrating the superior quality of the films. [ABSTRACT FROM AUTHOR]