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11.
A theoretical study is reported of the magnetic-field-controlled optical transmission through a stack of identical bilayers in which one layer is bigyrotropic and the other is nonmagnetic and isotropic. An analytical expression for the complex transmittance is derived. The transmittance–wavelength characteristic is examined for different magnetizations and for fixed materials parameters and total number of bilayers. The magnetization dependence of the position, height, and width of the center peak is investigated. The effect is calculated of magnetization on the ellipticity of transmitted light and the angle of optical rotation. 相似文献
12.
Translated from Steklo i Keramika, No. 1, pp. 11–12, January, 1992. 相似文献
13.
N. A. Cherkashin M. V. Maksimov A. G. Makarov V. A. Shchukin V. M. Ustinov N. V. Lukovskaya Yu. G. Musikhin G. E. Cirlin N. A. Bert Zh. I. Alferov N. N. Ledentsov D. Bimberg 《Semiconductors》2003,37(7):861-865
The effect of the growth temperature on the density, lateral size, and height of InAs-GaAs quantum dots (QD) has been studied by transmission electron microscopy. With the growth temperature increasing from 450 to 520°C, the density and height of QDs decrease, whereas their lateral size increases; i.e., the QDs are flattened. The blue shift of the photoluminescence line indicates decreasing QD volume. The observed behavior is in agreement with the thermodynamic model of QD formation. The effect of lowering the substrate temperature immediately after the formation of QDs on the QD parameters has been studied. On lowering the temperature, the lateral size of QDs decreases and their density increases; i.e., the parameters of QD arrays tend to acquire the equilibrium parameters corresponding at the temperature to which the cooling is done. The QD height rapidly increases with cooling and may exceed the equilibrium value for a finite time of cooling, which enables fabrication of QD arrays with a prescribed ratio between height and lateral size by choosing the time of cooling. 相似文献
14.
A method and algorithm of adaptive frequency measurements, and the flow diagram of a wide band adaptive computer data input module with frequency range from 7.6 mHz to 64.54 MHz are described.Translated from Izmeritel'naya Tekhnika, No. 3, pp. 18–20, March, 1995. 相似文献
15.
16.
We describe the simplest mechanism of cluster structure formation in the timefront of an acoustic signal propagating in a
submerged channel under ray chaos conditions. It is shown that this cluster structure is related to the phase space structure.
This relation allows, in principle, the characteristics of an inhomogeneous medium to be determined from the timefront shape
parameters. As an example, the period of inhomogeneity is calculated for a periodic perturbation in the sound velocity caused
by an internal wave propagation. 相似文献
17.
A. A. Karabutov V. A. Makarov V. L. Shkuratnik E. B. Cherepetskaya 《Journal of Mining Science》2003,39(4):323-330
Using the transfer function method as a base, the analytical relations are obtained, as well as the main parameters are calculated for the ultrasonic impulses of longitudinal, transverse, and the Rayleigh waves excited in geomaterials by laser emission. 相似文献
18.
V. V. Makarov 《Measurement Techniques》1996,39(5):545-549
A method of analyzing the accuracy and speed of adaptive measuring instruments based on two-parametric iteration algorithms
of amplitude adaptation in precision high-speed dc voltage measurements is discussed. The method makes it possible to estimate
the real and maximum attainable accuracy of adaptive dc voltage measurements over a wide dynamic range.
Translated from Izmeritel'naya Tekhnika, No. 5, pp. 49–51, May, 1996. 相似文献
19.
20.
Reinhold Ludwig Sergey Makarov Diran Apelian 《Journal of Nondestructive Evaluation》1998,17(3):153-166
This paper investigates electrostatic voltage distributions around a surface-breaking flaw due to an injected current of known
strength. The direct 3-D solution of the voltage behavior over the flawed surface is obtained numerically by the use of a
boundary integral formulation. A novel iteration method is applied to solve the resulting electrostatic integral equation
for the unknown surface voltage distribution. In addition to investigating the sensitivity of different flaw sizes to the
observed surface voltage distribution, important issues such as suitable probe spacing and current flow orientation are studied.
For sufficiently small surface-breaking flaws, a simple image source model is developed to evaluate the voltage response of
hairline cracks. The model is tested by comparing it with the developed numerical solution. Experiments aimed at establishing
the validity of the modeling approach show remarkable agreement with the theoretical model. 相似文献