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D. G. Pavel’ev N. V. Demarina Yu. I. Koshurinov A. P. Vasil’ev E. S. Semenova A. E. Zhukov V. M. Ustinov 《Semiconductors》2004,38(9):1105-1110
Characteristics of ohmic InGaAs contacts in planar diodes based on semiconductor superlattices with a small-area active region
(1–10 μm2) are studied. The diodes were formed on the basis of short (18 or 30 periods) heavily doped (1018 cm−3) GaAs/AlAs superlattices with a miniband width of 24.4 meV. The reduced resistance of the ohmic contact was equal to 2×10−7 Ω cm2 at room temperature. It is shown that the properties of fabricated planar diodes make it possible to use these diodes later
on in semiconductor devices that operate in the terahertz frequency region in a wide temperature range (4–300 K).
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Translated from Fizika i Tekhnika Poluprovodnikov, Vol. 38, No. 9, 2004, pp. 1141–1146.
Original Russian Text Copyright ? 2004 by Pavel’ev, Demarina, Koshurinov, Vasil’ev, Semenova, Zhukov, Ustinov. 相似文献
3.
L. G. Gerchikov Yu. A. Mamaev A. V. Subashiev Yu. P. Yashin D. A. Vasil’ev V. V. Kuz’michev A. E. Zhukov E. S. Semenova A. P. Vasil’ev V. M. Ustinov 《Semiconductors》2006,40(11):1326-1332
Photoemission of polarized electrons from heterostructures based on InAlGaAs/GaAs superlattices with minimum conduction-band offsets is investigated. The comparison of the excitation energy dependence of the photoemission polarization degree with the calculated spectra make it possible to determine the polarization losses at different stages of the photoemission. A maximum polarization of P = 91% and a quantum yield of 0.14% are close to the best results obtained for photocathodes on the basis of strained semiconductor superlattices. 相似文献
4.
L. Ya. Karachinsky T. Kettler N. Yu. Gordeev I. I. Novikov M. V. Maximov Yu. M. Shernyakov N. V. Kryzhanovskaya A. E. Zhukov E. S. Semenova A. P. Vasil’ev V. M. Ustinov N. N. Ledentsov A. R. Kovsh V. A. Shchukin S. S. Mikhrin A. Lochmann O. Schulz L. Reissmann D. Bimberg 《Semiconductors》2005,39(12):1415-1419
Lasers based on InAs/InGaAs quantum dots grown on metamorphic (In,Ga,Al)As layers deposited by MBE on GaAs substrates exhibited emission near 1.5 μm with a differential quantum efficiency of about 50%. The narrow-stripe lasers operate in a single transverse mode and withstand continuous current density above 20 kA cm?2 without significant degradation. A maximum continuous-wave output power of 220 mW is obtained. Neither current nor beam filamentation was observed up to the highest pumping levels. 相似文献
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The various complex mathematical transformations previously proposed for eliminating methodological errors of multicolor radiation pyrometry are mainly reduced to the determination of such combinations of wavelengths or corrections of registered brightness for the spectral distribution of the radiating capacity of the object being thermometered at which its equivalent radiating capacity is equal to unity. Mathematical formulas of the determining parameters of multicolor pyrometry of radiation have been obtained. Engineering techniques for calculating the critical values of the determining and adjustable parameters at which the application of multicolor optical thermometry is excluded because of large errors have been developed. Algorithms of a priori and a posteriori calibration systems of multicolor pyrometry of radiation of objects with practically any spectral distribution of the radiating capacity are proposed. 相似文献
8.
V. P. Zhukov 《Chemical and Petroleum Engineering》1992,28(1):32-34
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 1, pp. 17–18, January, 1992. 相似文献
9.
Fast, realistic lighting for video games 总被引:3,自引:0,他引:3
A novel, view-independent technology produces natural-looking lighting effects faster than radiosity and ray tracing. The approach is suited for 3D real-time interactive applications and production rendering. 相似文献
10.
I. I. Novikov N. Yu. Gordeev M. V. Maksimov Yu. M. Shernyakov E. S. Semenova A. P. Vasil’ev A. E. Zhukov V. M. Ustinov G. G. Zegrya 《Semiconductors》2005,39(4):481-484
Semiconductor laser heterostructures containing five and ten sheets of InAs/GaAs QDs on GaAs substrates, with an emission wavelength of ~1.3 μm, have been studied. Dependences of the nonradiative lifetime and effective Auger coefficient in QDs are obtained from an analysis of temperature and current dependences of the efficiency of spontaneous radiative recombination. The zero-threshold Auger recombination channel in QDs is shown to dominate at low (below 200 K) temperature, whereas at higher temperatures the quasithreshold channel becomes dominant. The effective 3D Auger coefficient is estimated in the approximation of a spherical QD, and a good agreement with the experimental data is obtained. 相似文献