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751.
Boikov Yu. A. Lil’enfors T. Olsson E. Klaeson T. Danilov V. A. 《Physics of the Solid State》2011,53(10):2168-2173
A significant (∼1.8%) positive unit between the parameters of the crystal lattice is the reason of tetragonal distortion (a
⊥/a
‖ ≈ 1.04) and reduction in the volume of the unit cell of La0.67Ca0.33MnO3 films (15 nm) quasicoherently grown on the (001) surface of a LaAlO3 substrate. The films consist of single-crystal blocks with the lateral size of 30–50 nm. The atomically smooth LaAlO3-La0.67Ca0.33MnO3 interphase boundary has no misfit dislocations. At T = 4.2 K, the transformation of nonferromagnetic phase inclusions into ferromagnetic ones in a constant magnetic field H is accompanied by a stable reduction in the electrical resistivity ρ of manganite films with time, so that the curve ρ(t) is well approximated by the relationship ρ(t) ∼ ρ1(t − t
0)1/2, (where t
0 is the time for establishment of the specified value (μ0
H = 5 T) of the magnetic field and ρ1 is a coefficient independent of H). The magnetocrystalline anisotropy due to the elastic deformation of films by the substrate and stratification of electronic
phases are the reasons of the distinct hysteresis in the dependences ρ(μ0
H, T < 100 K) obtained on μ0
H scanning in the sequence 5 T → 0 → −5 T → 0 → 5 T. At T = 50 K and μ0
H = 0.4 T, the magnetoresistance MR = 100% [ρ(μ0
H) − ρ(μ0
H = 0)]/ρ(μ0
H = 0) of LCMO films attains 150%. 相似文献
752.
Kudryashov S. I. Danilov P. A. Sdvizhenskii P. A. Lednev V. N. Chen J. Ostrikov S. A. Kuzmin E. V. Kovalev M. S. Levchenko A. O. 《JETP Letters》2022,115(5):251-255
JETP Letters - A spontaneous Raman signal at the frequency of the triply degenerate optical phonon of diamond is observed in the photoluminescence spectrum under the pre-filamentation excitation of... 相似文献
753.
Choi SK Olsen SL Adachi I Aihara H Aulchenko V Aushev T Aziz T Bakich AM Balagura V Bedny I Bitenc U Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Dalseno J Danilov M Dash M Eidelman S Gabyshev N Golob B Haba J Hara T Hayasaka K Hayashii H Hazumi M Heffernan D Hoshi Y Hou WS Hyun HJ Iijima T Inami K Ishikawa A Ishino H Itoh R Iwasaki M Iwasaki Y Kah DH Kang JH Katayama N Kawai H Kawasaki T Kichimi H Kim HO Kim SK Kim YJ 《Physical review letters》2008,100(14):142001
A distinct peak is observed in the pi +/- psi' invariant mass distribution near 4.43 GeV in B-->K pi +/- psi' decays. A fit using a Breit-Wigner resonance shape yields a peak mass and width of M=4433+/-4(stat)+/-2(syst) MeV and Gamma=45-13+18(stat)-13+30(syst) MeV. The product branching fraction is determined to be B(B 0-->K -/+Z+/-(4430)) x B(Z+/-(4430)-->pi+/-psi')=(4.1+/-1.0(stat)+/-1.4(syst)) x 10(-5), where Z+/-(4430) is used to denote the observed structure. The statistical significance of the observed peak is 6.5 sigma. These results are obtained from a 605 fb(-1) data sample that contains 657 x 10(6) BB pairs collected near the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+ e- collider. 相似文献
754.
B. N. Zvonkov O. V. Vikhrova Yu. A. Danilov Yu. N. Drozdov A. V. Kudrin M. V. Sapozhnikov 《Bulletin of the Russian Academy of Sciences: Physics》2010,74(10):1434-1436
We show that the technique of pulsed laser sputtering of metallic manganese in a flow of hydrides (arsine or phosphine) allows
the deposition of half-metallic MnB
5 compound layers on GaAs (100) substrates. The crystal structure, magneto-optical, and galvanomagnetic properties of the layers
are determined by synthesis conditions, mainly by substrate temperature. It is established that the MnAs and MnP layers are
ferromagnetic at temperatures up to 300 K. 相似文献
755.
M.?V.?Dorokhin S.?V.?Za?tsev A.?S.?Brichkin O.?V.?Vikhrova Yu.?A.?Danilov B.?N.?Zvonkov V.?D.?Kulakovski? M.?M.?Prokof’eva A.?E.?Sholina 《Physics of the Solid State》2010,52(11):2291-2296
The circular polarization of low-temperature electroluminescence of diodes based on heterostructures with an undoped quantum
well InGaAs/GaAs and a delta〈Mn〉 layer in the GaAs barrier has been investigated. The possibility of changing the degree of
circular polarization of the electroluminescence by varying the main structural parameters of diodes (spacer layer thickness,
i.e., the distance between the delta〈Mn〉 layer and the quantum well, atomic concentration in the delta〈Mn〉 layer, and introduction
of an additional acceptor delta layer) has been analyzed. It has been revealed that the variation in the spacer layer thickness
is the most effective method for controlling the degree of circular polarization of the electroluminescence. 相似文献
756.
B. N. Zvonkov O. V. Vikhrova Yu. A. Danilov Yu. N. Drozdov A. V. Kudrin M. V. Sapozhnikov 《Physics of the Solid State》2010,52(11):2267-2270
The effect of elastic stresses (compressive, tensile) on the magnetic properties of epitaxial GaMnAs layers prepared by laser
deposition of solid-state targets in a gas atmosphere on different buffer sublayers (In
x
Ga1 − x
As and In
x
Ga1 − x
P) and substrates (GaAs, InP) has been investigated. It has been established from the investigations of magnetic-field dependences
of the Hall resistance that all layers exhibit ferromagnetic properties with the Curie temperature ∼50 K. It has been shown
that, in the case of tensile stresses in GaMnAs layers (In
x
Ga1 − x
As and In
x
Ga1 − x
P buffers and InP substrate), the anomalous Hall effect shape demonstrates a predominant orientation of the easy-magnetization
axis in the growth direction, unlike the GaMnAs layers prepared on a GaAs substrate (with compressive stresses), which demonstrate
the predominance of the component of the magnetization vector in the layer plane. 相似文献
757.
P. A. Danilov I. N. Saraeva S. I. Kudryashov A. P. Porfirev A. A. Kuchmizhak A. Yu. Zhizhchenko A. A. Rudenko S. F. Umanskaya D. A. Zayarny A. A. Ionin S. N. Khonina 《JETP Letters》2018,107(1):15-18
Donut-shaped visible (515 nm) femtosecond laser pulses with linear, radial and azimuthal polarizations after tight focusing (numerical aperture NA = 0.65) have been used for spectrally adjusted excitation of plasmonenhanced rhodamine 6G dye luminescence on the surface of a nanocrystalline 45-nm thick gold film with its plasmon resonance near the laser line. Significant luminescence output increments—1.7-fold for radial polarization compared to the azimuthal one, and almost 3-fold—compared to the linear one, have been observed. This effect is related to significant transformation of the transverse electrical field component into longitudinal one for radial polarization (up to 33% in intensity, according to our calculations), and corresponding increase in excitation efficiency of plasmons in the smaller nanocrystallites throughout the film. 相似文献
758.
G. I. Greisukh V. A. Danilov S. A. Stepanov A. I. Antonov B. A. Usievich 《Optics and Spectroscopy》2018,124(1):98-102
Results of studying the possibility to decrease the total depth of reliefs of a two-layer microstructure having two internal saw-tooth microreliefs reducing the dependence of the diffraction efficiency of the microstructure on the radiation wavelength and angle of radiation incidence on the microstructure are presented. These results allow one to minimize the complexity of obtaining optimum microrelief depths depending on requirements applicable to the diffraction optical element in the framework of the electromagnetic-diffraction theory. Optimum depths provide in the specified spectral range and interval of angles of radiation incidence the maximum possible (for the chosen width of the narrowest zone of the saw-tooth microrelief) value of the diffraction efficiency at the point of its minimum. 相似文献
759.
G. I. Greisukh V. A. Danilov S. A. Stepanov A. I. Antonov B. A. Usievich 《Optics and Spectroscopy》2018,125(2):232-237
Sawtooth microstructures with a relief depth significantly exceeding the central wavelength of the working spectral range are studied within the scalar and strict diffraction theories. The possibility of maintaining high diffraction efficiency, irrespective of the working spectral bandwidth and at allowed angles of incidence, which can reach 45° or more, is shown. It is also shown that the chromatism of such lenses is controlled in a very wide range and can be less than that of the lightest crown glasses. 相似文献
760.
Z. E. Kun’kova E. A. Gan’shina L. L. Golik Yu. A. Danilov A. V. Kudrin V. I. Kovalev G. S. Zykov Yu. V. Markin O. V. Vikhrova B. N. Zvonkov 《Physics of the Solid State》2018,60(5):943-949
GaMnAs layers grown by pulsed laser deposition were studied by magneto-optical transversal Kerr effect spectroscopy, spectral ellipsometry, resistivity and the Hall effect measurements, and magnetometry. The growth regimes for magnetically inhomogeneous layers containing Mn-enriched ferromagnetic regions with different composition and sizes were established. The layers grown at a temperature of 300°C exhibit a ferromagnetic behavior at temperatures below 80 K, which is conditioned by the presence of local ferromagnetic (Ga,Mn)As regions in the paramagnetic matrix. The nature of peculiarities in the TKE spectrum of these layers is discussed. 相似文献