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921.
Y. Sun G. D. Sanders F. V. Kyrychenko C. J. Stanton G. A. Khodaparast J. Kono Y. H. Matsuda N. Miura H. Munekata 《Physica E: Low-dimensional Systems and Nanostructures》2004,20(3-4):374
We present a theoretical and experimental study of electron-active cyclotron resonance in p-doped InMnAs in high magnetic fields. Results are based on an 8-band Pidgeon–Brown model generalized to include finite kz effects and s(p)–d exchange interaction between itinerant carriers and Mn d-electrons. The e-active transitions in the valence band in p-doped samples take place due to the nature of multiple valence bands (heavy and light holes). We have calculated the absorption spectra in high magnetic fields and identified optical transitions which contribute to the cyclotron resonance for both e-active and h-active polarizations. Calculations show agreement with experimental results. 相似文献
922.
L. Corradi A. M. Stefanini M. Trotta A. M. Vinodkumar S. Beghini G. Montagnoli F. Scarlassara G. Pollarolo 《Acta Physica Hungarica A》2004,19(1-2):95-100
A presentation of some recent significant results obtained in the field of multinucleon transfer reactions at Coulomb barrier energies is given. The comparison of the experimental observables with the predictions of theoretical models treating quasi-elastic and deep-inelastic processes on the same ground reveals interesting features of the reaction mechanisms not clearly identified in the past. 相似文献
923.
A. N. Vasiliev V. N. Grishin A. M. Davidenko A. A. Derevschikov Yu. A. Matulenko Yu. M. Melnik A. P. Meschanin V. V. Mochalov L. V. Nogach S. B. Nurushev A. F. Prudkoglyad P. A. Semenov L. F. Soloviev V. L. Solovianov V. Yu. Khodyrev K. E. Shestermanov A. E. Yakutin N. S. Borisov V. N. Matafonov A. B. Neganov Yu. A. Plis Yu. A. Usov A. N. Fedorov A. A. Lukhanin 《Physics of Atomic Nuclei》2004,67(8):1487-1494
Results are presented that were obtained by measuring single-spin asymmetry in the inclusive production of neutral pions in the reaction p+p ↑→ π 0+X at x F≈0. A beam of 70-GeV protons was extracted directly from the vacuum chamber of the accelerator by means of a bent single crystal. For transverse momenta in the range 1.0<p T<3.0 GeV/c, the single-spin asymmetry independently measured by two detectors is zero within the errors. This result is in agreement with Fermilab data obtained at 200 GeV, but it is at odds with CERN data measured at 24 GeV. 相似文献
924.
V. M. Kalita A. F. Lozenko S. M. Ryabchenko P. A. Trotsenko T. M. Yatkevich 《Physics of the Solid State》2004,46(2):326-334
The forced magnetostriction and magnetization are measured in the easy-plane-type two-sublattice NiCl2 antiferromagnet (AFM) in the case where this AFM passes from the multidomain to a single-domain state. It is shown that, in accordance with the magnetoelastic nature of the multidomain state, the field dependences of the forced magnetostriction and magnetization are interrelated and affected by the transition from the multidomain to the single-domain state. The character of these dependences corresponds to the case where the magnetization and striction are proportional to the number of domains with an energetically favored orientation with respect to the external magnetic field. 相似文献
925.
S. N. Grinyaev F. V. Konusov V. V. Lopatin L. N. Shiyan 《Physics of the Solid State》2004,46(3):435-441
The pseudopotential and supercell methods are used to study the optical absorption of graphite-like hexagonal boron nitride involving deep levels of nitrogen vacancies and their clusters. The impurity-induced absorption is shown to be mainly related to electron transitions between the states that are antisymmetric with respect to the horizontal plane. Therefore, this absorption is highly anisotropic and is maximum for light waves polarized normally to the hexagonal axis. The optical absorption and photoconductivity spectra before and after neutron irradiation and thermal treatment are interpreted, and the activation energies for the thermoluminescence and conductivity of nitrogen-depleted boron nitride before and after fast-neutron irradiation and vacuum annealing are found. 相似文献
926.
V. E. Pukha V. V. Varganov I. F. Mikhailov A. N. Drozdov 《Physics of the Solid State》2004,46(8):1574-1576
The effect of a bismuth sublayer with an effective thickness of 0.5 to 4 nm on the structure of C60 fullerene films grown on amorphous substrates (silicon covered with a natural oxide layer; glass) using the quasi-closed-volume method is studied. An x-ray diffraction study of fullerene films showed that the intensity ratio between the (220) and (111) peaks depends nonmonotonically on the sublayer thickness. In the bismuth sublayer thickness range 0.5–2.0 nm, fullerene films are found to exhibit a growth texture with the 〈110〉 axis; the average crystallite size was ~20 µm. The quality of the texture can be improved by varying the fullerene growth temperature. 相似文献
927.
V. F. Tarasenko S. B. Alekseev V. M. Orlovskii V. G. Shpak S. A. Shunailov 《Technical Physics》2004,49(8):982-986
Conditions are studied under which an electron beam and a volume discharge with a subnanosecond rise time of a voltage pulse
are produced in air under atmospheric pressure. It is shown that the electron beam appears in a gas-filled diode at the front
of the voltage pulse in ∼0.5 ns, has a half-intensity duration of ≤0.4 ns and an average electron energy of ∼0.6 of the voltage
across the gas-filled diode, and terminates when the voltage across the gap reaches its maximum value. The electron beam with
an average electron energy of 60 to 80 keV and a current amplitude of ≥70 A is obtained. It is assumed that the electron beam
is formed from electrons produced in the gap due to gas ionization by fast electrons when the intensity of the field between
the front of the expanding plasma cloud and the anode reaches its critical value. A nanosecond volume discharge with a specific
power input of ≥400 MW/cm3, a density of the discharge current at the anode of up to 3 kA/cm2, and specific energy deposition of ∼1 J/cm3 over 3 to 5 ns is created. 相似文献
928.
The effect of uniform pressure on the character of metal-dielectric transitions in compensated weakly- and highly doped semiconductors (WHDCS) is considered. The influence of hybridization of resonance quasilocalized impurity states with band continuum states on the transition is shown. Minimum metallic conductivities in p-CdSnAs2 are determined for Mott and Anderson transitions. Special features of the metal-dielectric transformation in weakly-doped narrow- and high energy-gap semiconductors are discussed for the case of hydrogen-like impurities. Anderson localization in WHDCS is also considered. Phase diagrams are presented. 相似文献
929.
930.