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J. P. B. Silva A. Khodorov A. Almeida J. Agostinho Moreira M. Pereira M. J. M. Gomes 《Applied Physics A: Materials Science & Processing》2014,116(3):1271-1280
In this work, Ba0.8Sr0.2TiO3 (BST) films were grown by pulse laser ablation on bare glass and platinized substrates. The crystalline phase was obtained with the help of laser-assisted annealing (LAA) at room temperature, in air environment. By adjusting LAA conditions, like frequency of the laser and number of shots, we were able to grow crack-free BST thin films with pure perovskite phase on bare glass and platinized substrates. The crystalline layer was found to be the same irrespective of the substrate used, c.a. 250 nm thick. The electric characteristics of the amorphous and LAA crystalline BST films deposited on platinized substrate were further studied and analyzed. While in amorphous films it was found that the oxygen defects are responsible for conduction, in LAA films the amorphous/crystalline interface layer plays an important role in current leakage. 相似文献
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The paper investigates the Galerkin method for an initial boundary value problem for heat convection equations. New error
estimates for the approximate solutions and their derivatives in strong norm are obtained. 相似文献
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Anupama Yadav Cameron Glasscock Leonid Chernyak Igor Lubomirsky Sergey Khodorov 《辐射效应与固体损伤》2016,171(3-4):223-230
The impact of 60Co gamma-irradiation on n-channel AlGaN/GaN high-electron-mobility transistors was studied by means of temperature-dependent electron beam-induced current (EBIC) and cathodoluminescence (CL) techniques. For the doses up to ~250?Gy, an enhancement of minority carrier transport was observed as evident from the EBIC measurements. This enhancement is associated with internal electron irradiation induced by the primary gamma photons. For the doses above ~250?Gy, deterioration in minority carrier transport was explained by carrier scattering on radiation-induced defects. It is shown that calculated activation energy from the EBIC and CL measurements follows exactly the same trend, which implies that the same underlying phenomenon is responsible for observed findings. 相似文献
45.
We study the property of finiteness of a support for a system of evolutionary equations and for equations with nonstationary
p-Laplacian and with convective terms. New bounds of the size of the support with regard for the convective terms are obtained. 相似文献
46.
We consider reaction-diffusion systems in unbounded domains, prove the existence of expotential attractors for such systems, and estimate their fractal dimension. The essential difference with the case of a bounded domain studied before is the continuity of the spectrum of the linear part of the equations. This difficulty is overcome by systematic use of weighted Sobolev spaces. 相似文献
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We introduce here a new “neoclassical” electromagnetic (EM) theory in which elementary charges are represented by wave functions
and individual EM fields to account for their EM interactions. We call so defined charges balanced or “b-charges”. We construct
the EM theory of b-charges (BEM) based on a relativistic field Lagrangian and show that: (i) the elementary EM fields satisfy
the Maxwell equations; (ii) the Newton equations with the Lorentz forces hold approximately when b-charges are well separated
and move with non-relativistic velocities. When the BEM theory is applied to atomic scales it yields a hydrogen atom model
with a frequency spectrum matching the Schrodinger model with desired accuracy. An important feature of the theory is a mechanism
of elementary EM energy absorption established for retarded potentials. 相似文献