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41.
42.
Renk KF Stahl BI Rogl A Janzen T Pavel'ev DG Koshurinov YI Ustinov V Zhukov A 《Physical review letters》2005,95(12):126801
We report a superlattice parametric oscillator (SPO), with a GaAs/AlAs superlattice as the active element. The SPO was pumped by a microwave field (power 4 mW) and produced third harmonic radiation at subterahertz frequencies (near 300 GHz; 0.1 mW). We attribute the parametric gain to the nonlinearity of the miniband transport. 相似文献
43.
Meister M Chulkov LV Simon H Aumann T Borge MJ Elze TW Emling H Geissel H Hellström M Jonson B Kratz JV Kulessa R Leifels Y Markenroth K Münzenberg G Nickel F Nilsson T Nyman G Pribora V Richter A Riisager K Scheidenberger C Schrieder G Tengblad O Zhukov MV 《Physical review letters》2003,91(16):162504
The one-proton knockout channel from 6He (240 MeV/u) impinging on a carbon target has been investigated. The triton fragments originating from this channel were detected in coincidence with the two neutrons. A broad structure, peaked at 3 MeV above the t+2n threshold, is observed in the t+n+n-relative energy spectrum. It is shown that this structure is mainly due to a I(pi)=1/2(+) resonance as expected for the 5H ground state, and from the observed angular and energy correlations, being used for the first time in 5H studies, that the neutrons to a large extent occupy the p shell. 相似文献
44.
We report a direct experimental observation and provide a theory of the distribution of trajectories along which a fluctuating system moves over a potential barrier in escape from a metastable state. The experimental results are obtained for a semiconductor laser with optical feedback. The distribution of paths displays a distinct peak, which shows how the escaping system is most likely to move. We argue that the specific features of this distribution may give an insight into the nature of dropout events in lasers. 相似文献
45.
D.C. Gonzalez M.E. Kiziroglou X. Li A.A. Zhukov H. Fangohr P.A.J. de Groot P.N. Barttlet C.H. de Groot 《Journal of magnetism and magnetic materials》2007
We have succeeded in aligning self-assembled structures by using a lithographically defined stripe. The 140 nm wide by 100 nm high SiO2 strip is shown to guide the assembly of 500 nm latex spheres so that spheres are aligned along the strip and are in registration on either side of the strip. This method can be used to increase long-range ordering in magnetic storage systems without compromising the density. Inverse sphere Ni arrays were made by electrodeposition through the latex template. We also show that the hexagonal symmetry of the resulting inverse sphere Ni arrays can be simulated using the approach presented below. 相似文献
46.
I. A. Kiiko A. V. Muravlev A. N. Sakharov P. V. Chistyakov S. V. Novotnyi A. I. Zhukov 《Moscow University Mechanics Bulletin》2011,66(6):135-137
The experimental and numerical study of the strain state is conducted for the spire of the Moscow University main building.
The experimental data are in good agreement with the numerical results obtained according to a finite-element beam model of
the spire. 相似文献
47.
48.
A. S. Zhukov V. A. Arkhipov S. S. Bondarchuk V. D. Gol’din 《Russian Journal of Physical Chemistry B, Focus on Physics》2013,7(6):777-782
A physicomathematical model of thermal and diffusion processes in a drop of a dilute metal salt solution during its heating in a plasma-chemical reactor for synthesizing metal oxide powders is presented. The results of numerical calculations are analyzed to assess the possible influence of the operation parameters of the reactor and the characteristics of the initial solution (precursor) on the morphology of the particles formed. 相似文献
49.
A. D. Balaev É. G. Zhukov N. B. Ivanova N. V. Kazak S. G. Ovchinnikov E. P. Popel 《Physics of the Solid State》2001,43(6):1089-1092
The region of the concentration magnetic phase transition in a CuxZn1?x Cr2Se4 chalcogenide spinel in which the substituted ion concentration x smoothly varies from 0.1 to 0.2 with a step of 0.02 is thoroughly investigated. An anomalous behavior of the Curie temperature is observed. This anomaly is associated with the nucleation of ferromagnetically ordered microregions in the vicinity of Cr ions with an intermediate valence and subsequent long-range magnetic ordering at a critical Cu concentration in the range 0.12<x c <0.14. The possible coexistence of ferro-and antiferromagnetism in the same temperature range is revealed. 相似文献
50.
For arcs with zirconium cathodes in nitrogen, experimental results are presented about changes of material and structure of the cathode, temperature fields, current densities, heat flows, electron work function and erosion rate. The cathode heat regime is described theoretically. In the experiments, the arc current was 50–200 A. 相似文献