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1.
Galia Pozina Elizaveta I. Girshova Konstantin M. Morozov Konstantin A. Ivanov Anton Yu. Egorov Mikhail A. Kaliteevski 《Annalen der Physik》2019,531(6)
Enhancement of spontaneous emission in a resonant Bragg quantum well (QW) structure with 60 periods of triple InAs monolayers embedded in a GaAs matrix is studied experimentally and theoretically. From measurements of the time‐resolved photoluminescence, besides the QW exciton at 1.47 eV, a specific super‐radiant (SR) emission demonstrating nonlinear properties is found. The SR mode shows a near‐quadratic dependence of intensity on excitation power, while its energy position follows the Bragg condition. It is revealed that the SR mode shows a peculiar non‐monotonic dependence of intensity on direction, with a maximum observed at approximately 40°. The enhancement in the SR emission at a specific direction is correlated well with suggested theoretical consideration of the modal Purcell factor for periodic quantum well structures. 相似文献
2.
S. A. Egorov 《Technical Physics》2006,51(8):999-1003
Calorimetric studies of titanium nickelide show that thermally reversible prestraining does not affect the heat of the B2 → R and R → B2 martensitic transformations. At the same time, reactive stresses induced by straining under constrained conditions are found to decrease the heat of the B19′ → B2, R → B19′, B2 → R, and R → B2 transformations by a factor of 1.16–1.40. A formula describing this effect is proposed. 相似文献
3.
The mechanism of X-ray waveguide-resonance propagation or the radiation superstream model, which can become the ground of X-ray nanophotonics, is discussed briefly. Some attention is devoted to features consideration of the simplest devices characterized by the waveguide-resonance transportation of X-ray beams. The experimental data showing the user possibilities of a simplest waveguide-resonators application for diffractometry are presented. We discuss the main reasons to improve the metrological characteristics for total reflection X-ray fluorescence (TXRF) analytical method in case when the target exciting beam is formed by a waveguide-resonator. Some problems appearing during the waveguide-resonator application are formulated. 相似文献
4.
V. A. Egorov 《Journal of Mathematical Sciences》1987,36(4):476-481
One finds conditions for the relation
are the absolute order statistics for a repeated sample from a symmetric distribution.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 142, pp. 59–67, 1985. 相似文献
5.
The effect of diatomite on the inflammability, combustibility, and smoke-forming ability of poly(vinyl chloride)-based plastisols has been studied. A substantial decrease in these characteristics takes place upon the introduction of 2–3% diatomite as compared with 10–15% for vermiculite and phlogopite fillers. This phenomenon is associated with a high viscosity of the plastisol melt filled with diatomite and its better foaming and carbonization, along with the formation of a high-porosity coke demonstrating heat-shielding behavior. The use of diatomite also improves the mechanical properties of the tested material. 相似文献
6.
7.
The maximal hypoellipticity of the operator X
1
2m
, ... X
k
2m
is proved, where Xj are first-order pseudodifferential operators and m is a natural number. It is assumed that the set of these operators and
their first-order commutators is an elliptic system. The results obtained generalize the well-known results of Hormander,
Oleinik, and Radkevich, Kohn, Helffer, and Nourrigat, and Rothshield and Stein. Bibliography: 9 titles.
Translated from Trudy Seminara imeni I. G. Petrovskogo, No. 17, pp. 3–26, 1994. 相似文献
8.
V. A. Egorov 《Journal of Mathematical Sciences》1988,43(6):2791-2796
LetP
a be the class of those partitions of intervals [,T], such that |t
i
–t
i–1
|>a, wherea is a constant,
. It is proved that for anya lim V(T,P
a
)/2Tln
2T=1 a. s., whereln
i
x=ln ln x, ifln x e,ln
2
x=1, ifln x <e.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 158, pp. 72–80, 1987. 相似文献
9.
10.