Engineering topics

Klimov, A. A.

Publications and source records attributed to Klimov, A. A..

3 records

DOE OSTI2020

Leaky wave in high-power AlGaAs/InGaAs/GaAs semiconductor lasers

Lasers based on AlGaAs/InGaAs/GaAs heterostructures operating in the spectral range of 1.0 − 1.1 μm are investigated in order to optimise cladding layers. The effect of the thickness and composition of the cladding layers on the leakage of radiation from the laser waveguide is analysed. It is shown that for cladding thicknesses of 0.86 − 1.24 μm, it almost does not affect the output optical power. The effect of the crystal length and reflectivity of the laser mirrors on the leaky wave is demonstrated. (paper)

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

DOE OSTI2019

Magnetic Interactions on Oxide Ferromagnet/Ferromagnetic Intermetallide Interface

The magnetic properties of heterostructures consisting of two films are studied. The upper layer involves rare-earth intermetallic nanostructured superlattices consisting of exchange-coupled layers (TbCo{sub 2}/FeCo){sub n} (TCFC), and the lower layer includes either epitaxial manganite La{sub 0.7}Sr{sub 0.3}MnO{sub 3} (LSMO) with optimum strontium doping or an epitaxial film of an yttrium–iron garnet Y{sub 3}Fe{sub 5}O{sub 12} (YIG) with a Bi additive. TCFC is a ferromagnet having high Curie temperature and provides controllable induced magnetic anisotropy. Experimental studies showed that the interlayer interaction of the TCFC/LSMO heterostructure is antiferromagnetic. There was an increase in the FMR line width in the structures due to the flow of a spin current through the interface between two films. There was electric voltage in the TCFC/YIG heterostructure induced in the TCFC intermetallide film, due to an inverse spin Hall effect under ferromagnetic resonance conditions.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

DOE OSTI2019

Conductivity of Manganite Films under the Action of Tension Caused by the Deformation of Substrate

The electron transport properties of strained thin La{sub 0.7}Ba{sub 0.3}MnO{sub 3} (LBMO) epitaxial films are studied. Films 40–100 nm in thickness were prepared by laser ablation at a temperature T = 700–800°C in pure oxygen atmosphere of 0.3–1 mBar. Ferroelectric crystal substrates (011)0.79PbMg{sub 1/3}Nb{sub 2/3}O{sub 3}–0.21-PbTiO{sub 3} (PMN–PT) with a Curie temperature of 150°C and high piezoelectric constants were used to create a mechanical stress. The ferroelectric polarization and piezoelectric effects on the electrical parameters of LBMO films are studied.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗