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981.
A. F. G. Monte M. A. G. Soler S. W. da Silva B. B. D. Rodrigues P. C. Morais A. A. Quivy J. R. Leite 《Physica E: Low-dimensional Systems and Nanostructures》2004,23(3-4):466
We have investigated the influence of vicinal GaAs substrates on the optical and electronic properties of InGaAs/GaAs quantum wells (QWs). A single In0.10Ga0.90As QW was grown by molecular-beam epitaxy on a vicinal GaAs(0 0 1) substrate with a miscut angle of 0° (nominal), 2°, 4° and 6° towards [1 1 0]. The carrier diffusion was obtained by a micro-photoluminescence scan technique that permits to observe the effective diffusion length characterized by the lateral spread of carriers in the QW followed by radiative recombination. The carrier diffusion length was obtained parallel (L||) and perpendicular (L) to the atomic steps. The diffusion length decreases as the temperature increases up to 100 K. Above this temperature we found different behaviours that depend on the sample miscut angle. 相似文献
982.
983.
Phonon scattering from the boundaries of small crystals embedded in a dielectric porous-glass matrix
L. S. Parfen’eva I. A. Smirnov A. V. Fokin H. Misiorek J. Mucha A. Jezowski 《Physics of the Solid State》2003,45(2):381-385
The thermal conductivity of porous glass with randomly distributed connecting pores ~70 Å in size (glass porosity ~25%), as well as of a porous glass + NaCl composite, was measured in the temperature range 5–300 K. NaCl filled one fourth of the pores in the composite. The experimental results on the composite thermal conductivity can be accounted for only by assuming that phonons scatter from the boundaries of NaCl nanocrystals embedded in channels of the porous glass. 相似文献
984.
985.
986.
It is usually assumed, in classical statistical mechanics, that the temperature should coincide, apart from a suitable constant factor, with the mean kinetic energy of the particles. We show that this is not the case for Fermi–Pasta–Ulam systems, in conditions in which energy equipartition between the modes is not attained. We find that the temperature should be rather identified with the mean value of the energy of the low frequency modes. 相似文献
987.
Bruzón M. S. Gandarias M. L. Muriel C. Ramírez J. Saez S. Romero F. R. 《Theoretical and Mathematical Physics》2003,137(1):1367-1377
We use the classical and nonclassical methods to obtain symmetry reductions and exact solutions of the (2+1)-dimensional integrable Calogero–Bogoyavlenskii–Schiff equation. Although this (2+1)-dimensional equation arises in a nonlocal form, it can be written as a system of differential equations and, in potential form, as a fourth-order partial differential equation. The classical and nonclassical methods yield some exact solutions of the (2+1)-dimensional equation that involve several arbitrary functions and hence exhibit a rich variety of qualitative behavior. 相似文献
988.
A. N. Dovbnya K. V. Korytchenko M. A. Krasnogolovets Yu. Ya. Volkolupov Yu. D. Tur S. M. Shkirida A. I. Kosoi 《Technical Physics》2003,48(12):1586-1589
The influence of the discharge conditions on the dynamics of energy release is considered for pulsed arcs in air at initial pressures from 105 to 8×105 Pa and a low-voltage capacitor voltage of up to 400 V. A novel method for determining the resistance of the discharge channel in the final stage of a spark discharge is proposed. The method is applied to estimating the discharge channel parameters. 相似文献
989.
Periodica Mathematica Hungarica - 相似文献
990.
A holographic screen that makes it possible to display 3D images by the method of point-focused aspects (of a scene to be displayed) or by projecting narrow line holograms is suggested and implemented. The image thus formed reconstructs only horizontal parallax, which allows one to cut the body of information necessary for 3D imaging. Projection through the screen and a way of recording the screen are considered. 相似文献