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91.
A. Yu. Andreev A. Yu. Leshko A. V. Lyutetskiĭ A. A. Marmalyuk T. A. Nalyot A. A. Padalitsa N. A. Pikhtin D. R. Sabitov V. A. Simakov S. O. Slipchenko M. A. Khomylev I. S. Tarasov 《Semiconductors》2006,40(5):611-614
Symmetric and asymmetric separate-confinement AlGaAs/GaAs heterostructures have been grown by MOCVD in accordance with the
concept of design of high-power semiconductor lasers. High-power laser diodes with a 100-μm aperture, emitting in the 808–850-nm
range, were fabricated from these structures. The internal optical loss in asymmetric separate-confinement heterostructures
with broadened waveguide is reduced to 0.5 cm−1. In the lasers with 1.7-μm-thick waveguide, the output optical power of 7.5 W in CW mode was achieved owing to reduction
of the optical emission density at the cavity mirror to 4 mW/cm2.
Original Russian Text ? A.Yu. Andreev, A.Yu. Leshko, A.V. Lyutetskiĭ, A.A. Marmalyuk, T.A. Nalyot, A.A. Padalitsa, N.A. Ptkhtin,
D.R. Sabitov, V.A. Simakov, S.O. Slipchenko, M.A. Khomylev, I.S. Tarasov, 2006, published in Fizika i Tekhnika Poluprovodnikov,
2006, Vol. 40, No. 5, pp. 628–632. 相似文献
92.
A. F. Andreev 《Journal of Superconductivity》1999,12(1):197-207
The nature of superfluid, superconducting, and magnetic ordering is elucidated for mesoscopic systems in which the single-particle level spacing is much larger than both the temperature and the critical temperature of ordering. Ordering is defined as a spontaneous breaking of symmetry, the gauge invariance and time reversal being by definition symmetries broken in superfluidity (superconductivity) and magnetism contexts, respectively. Superfluidity and superconductivity are realized in thermodynamic equilibrium states with a nonintegral average number of particles and are accompanied by the spontaneous breaking of time homogeneity. In Fermi systems, two types of superfluidity and superconductivity are possible which are characterized by the presence of pair or single-particle condensates. The latter is remarkable in that spontaneous breaking of fundamental symmetries such as spatial 2 rotation and double time reversal takes place. Possible experiments on metallic nanoparticles and ultracold atomic gases in magnetic traps are discussed. 相似文献
93.
The effect of a magnetic field and surfactants on the rheological properties of strontium ferrite suspensions has been studied. An applied magnetic field is shown to raise the suspension viscosity, which is attributable to the formation of three-dimensional chain structures made up of ferrite particles. After the magnetic field is removed, these structures do not fully break down, which leads to hysteretic behavior of the suspension viscosity. The introduction of polyelectrolytes reduces the viscosity of the suspension both in a magnetic field and after the field is removed. This is due to the formation of an electrical double layer on the particle surface, which reduces interparticle friction and the strength of the three-dimensional structures. The results of this study may be useful in devising processes for enhancing the texture and density of highly anisotropic strontium ferrite materials produced by wet pressing. 相似文献
94.
A. N. D’yachenko A. A. Andreev A. S. Buinovskii R. I. Kraidenko 《Refractories and Industrial Ceramics》2006,47(3):146-148
An innovative method for preparation of mullite-based refractories from aluminosilicate topaz ores is proposed in which the
mineral ore is treated with ammonium fluoride; the excess silicon dioxide is removed in the form of gaseous ammonium hexafluorosilicate.
The desiliconized mixture is sintered to obtain a lightweight mullite refractory with a fibrous structure.
__________
Translated from Novye Ogneupory, No. 5, pp. 8–11, May, 2006. 相似文献
95.
Andreev N.F. Khazanov E.A. Kuznetsov S.V. Pasmanik G.A. Shklovsky E.I. Sidorin V.S. 《Quantum Electronics, IEEE Journal of》1991,27(1):135-141
Theoretical and experimental results obtained in the study of phase-locked conjugation of two light beams using a phase synchronizer demonstrate how phase conjugation of depolarized radiation can be used to compensate aberration and depolarization distortions in solid-state media. Two-beam phase conjugation via mutual scattering of orthogonally polarized pump waves under four-wave mixing is discussed. A novel analog operation-orthogonal phase conjugation (OPC)-involving an electromagnetic field was realized with a phase synchronizer 相似文献
96.
A. D. Andreev V. M. Borzdov A. A. Valiev O. G. Zhevnyak F. F. Komarov 《Journal of Engineering Physics and Thermophysics》1998,71(1):111-114
Based on results of measurement and processing of volt-ampere characteristics as well as linetic modeling of electron transfer
by the Monte Carlo method, the influence of the doping level and the temperature on electron mobility in the n channel of
a silicon MOS field-effect transistor operating in a linear regime is investigated.
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 71, No. 1, pp. 116–119, January–February, 1998. 相似文献
97.
1% acetylcholine (5.5 10 M--acetylcholine chloride) applied directly to the cortex of conscious non-immobilized rabbits was established to produce neuroglial reaction in motor area. Following 30 min long application the number of astrocytes was significantly increased. Application lasting for 2 hrs resulted in a reverse effect. The above-mentioned changes were observed in surface and deep cortical layers. They were functional and could be attributed to the cell tinctorial properties. 相似文献
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