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251.
A. I. Burkhanov P. V. Bondarenko S. I. Raevskaya A. V. Shil’nikov I. P. Raevskiĭ 《Physics of the Solid State》2006,48(6):1114-1116
The dielectric properties of a ceramic and a single crystal of the same composition 0.9NaNbO3-0.1Gd1/3NbO3 (NNG10) with different prehistories of the material are investigated in the low-and infralow-frequency ranges. It is revealed that the dielectric aging of the material based on the NaNbO3 antiferroelectric with a smeared phase transition differs in character from similar phenomena observed in relaxor ferroelectrics. 相似文献
252.
253.
254.
A model describing the initial stages of the local melting of grain boundaries containing impurity atom clusters is developed. The local melting process is considered as the formation of liquid zones whose geometry and number depend on the initial concentration and thermodynamic characteristics of the impurity atoms, as well as on the material parameters and temperature. The evolution of the liquid-solid interface structure with increasing temperature is discussed. The dependences of the liquid-solid interface parameters on temperature are obtained at various initial concentrations and thermodynamic characteristics of the impurity atoms. 相似文献
255.
A. G. Smol’nikov V. V. Ogloblichev S. V. Verkhovskii K. N. Mikhalev A. Yu. Yakubovskii K. Kumagai Y. Furukawa A. F. Sadykov Yu. V. Piskunov A. P. Gerashchenko S. N. Barilo S. V. Shiryaev 《JETP Letters》2015,102(10):674-677
The magnetically ordered phase of the CuCrO2 single crystal has been studied by the nuclear magnetic resonance (NMR) method on 53Cr nuclei in the absence of an external magnetic field. The 53Cr NMR spectrum is observed in the frequency range νres = 61–66 MHz. The shape of the spectrum depends on the delay tdel between pulses in the pulse sequence τπ/2–t del–τπ–t del–echo. The spin–spin and spin–lattice relaxation times have been measured. Components of the electric field gradient, hyperfine fields, and the magnetic moment on chromium atoms have been estimated. 相似文献
256.
V. Bradnova M. M. Chernyavsky L. Just S. P. Kharlamov A. D. Kovalenko M. Haiduc K. A. Kotel’nikov V. A. Krasnov V. G. Larionova F. G. Lepekhin A. I. Malakhov G. I. Orlova N. G. Peresadko N. G. Polukhina P. A. Rukoyatkin V. V. Rusakova N. A. Salmanova B. B. Simonov S. Vokal P. I. Zarubin 《Physics of Atomic Nuclei》2003,66(9):1646-1650
A physical program of irradiation of emulsions in beams of relativistic nuclei named the BECQUEREL Project is reviewed. It is destined to study in detail the processes of relativistic fragmentation of light radioactive and stable nuclei. The expected results would make it possible to answer some topical questions concerning the cluster structure of light nuclei. Owing to the best spatial resolution, the nuclear emulsions would enable one to obtain unique and evident results. The most important irradiations will be performed in the secondary beams of He, Be, B, C, and N radioactive nuclei formed on the basis of JINR Nuclotron beams of stable nuclei. We present results on the charged state topology of relativistic fragmentation of the 10B nucleus at low energy-momentum transfers as the first step of the research. 相似文献
257.
E. Yu. Lundina Yu. M. Shernyakov M. V. Maksimov I. N. Kayander A. F. Tsatsul’nikov N. N. Ledentsov A. E. Zhukov N. A. Maleev S. S. Mikhrin V. M. Ustinov Zh. I. Alferov D. Bimberg 《Technical Physics》2003,48(1):131-132
Accelerated degradation testing of long-wavelength (>1.25 µm) quantum-dot lasers made on GaAs substrates is carried out at a fixed current of 1.7 A, initial optical output of about 0.3 W, and a heat sink temperature of 60°C. No signs of degradation are revealed after testing for 450 h. The test bed is not sealed, inert gas purging is not performed, and the laser faces are not passivated. 相似文献
258.
A. G. Smol’nikov V. V. Ogloblichev A. F. Sadykov Yu. V. Piskunov A. P. Gerashchenko S. V. Verkhovskii A. Yu. Yakubovskii S. N. Barilo G. L. Bychkov S. V. Shiryaev 《Journal of Experimental and Theoretical Physics》2011,112(6):1020-1025
The NMR spectra and the decay of a spin echo signal from 51V nuclei in Kagome-staircase Co3V2O8 (CVO) and Ni3V2O8 (NVO) single crystals are measured in the temperature range 30–300 K and a magnetic field H
0 = 20 kOe. The orientation dependences of the 51V NMR line shape are used to determine the electric field gradient (EFG) parameters, namely, quadrupole frequency ν
Q
and asymmetry parameter η. These parameters for NVO and CVO are ν
Q
= 180(10) kHz, η = 0.5(1) and ν
Q
= 130(10) kHz, η = 0.6(1), respectively. A comparison of the results of calculating EFG tensors with a point charge model
and the NMR data indicates that the crystallographically equivalent vanadium atoms in the Ni3V2O8 and Co3V2O8 compounds differ in the EFG axis orientation. M3V2O8 crystals are found to have vanadium positions (V1, V2) with different orientations of the z axis, which specifies the direction of the principal value of EFG (V
zz
): these orientations lie in the bc plane and make an angle of either +51(5)° (V1) or −51(5)° (V2) with axis c. In the temperature range 30–300 K, the EFG tensor components and the local symmetry of the charge surrounding of the vanadium
positions in NVO and CVO oxides are found to change insignificantly. 相似文献
259.
Mel’nik N. N. Zavaritskaya T. N. Kucherenko I. V. Wojtowicz T. Janik E. Plyashechnik O. S. 《Physics of the Solid State》2011,53(8):1722-1726
The spectra of resonant light scattering by ZnTe quantum wires have been measured at excitation energies of 2.18–2.72 eV.
The quantum wires have been grown on Si(100) and GaAs(100) substrates by molecular beam epitaxy. The effect of outgoing resonance
with the electron transition energy E
0 on the intensity of phonon lines of the Stokes spectrum and on the intensity ratio of the Stokes and anti-Stokes spectral
lines has been studied. The energy E
0 has been determined in ZnTe and ZnMgTe quantum wires from the edge luminescence spectra. 相似文献
260.
Detailed calculations of eigenmodes of waveguiding structures made of silver and glass and containing coaxial cables with
a nanoscale cross section of different configurations are conducted. In particular, the study focuses on optical coaxial waveguides
with the core made in the form of a thin metallic cylinder filled with a dielectric. We show that these waveguides support
relatively low-loss propagation of radiation that is strongly localized in the central region, has phase velocity approaching
the speed of light and predominant electric-field orientation (dipole type). Optical characteristics of such waveguides are
compared with those of coaxial-type waveguides containing a continuous central filament made of metal and with a multilayer
structure. Using numeric modeling, we established that the proposed type of the waveguide enables the transmission of an optical
image with relatively low losses with a submicron resolution over a distance considerably longer than its cross section. A
typical propagation length in the waveguides based on silver and glass with the refractive index of about 1.5 at a wavelength
of 500 nm is about 1700 nm. 相似文献