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1.
In this work we briefly review the present day perspectives for exploiting conventional non-magnetic semiconductor nano-technology to design high speed spin-filter devices. In recent theoretical investigations a high spin polarization has been predicted for the ballistic tunneling current in semiconductor single- and double-barrier asymmetric tunnel structures of III–V semiconductors with strong Rashba spin–orbit coupling. We show in this paper that the polarization in the tunneling can probability be sufficiently increased for producing realistic single-barrier structures by including of the Dresselhaus term into consideration. 相似文献
2.
I. A. Ivanova V. T. Astrelin A. V. Burdakov R. V. Voskoboynikov A. I. Gorbovskii A. A. Ivanov V. A. Kapitonov S. G. Konstantinov K. N. Kuklin S. V. Polosatkin M. A. Tiunov 《Bulletin of the Lebedev Physics Institute》2009,36(11):325-326
To provide basic operations of semiconductor and radiation materials technologies, a multipurpose implanter with intense ion beams was developed at the Institute of Nuclear Physics. The generated beamparameters are as follows: ions are H+, O+; C+; the ion energy is up to 200 keV; the beam current is up to 2 mA; and the implantation mode is continuous. The size of the target to be processed can reach 76 × 76 mm2. During the implanter operation, the target chamber vacuum reaches 10?4 Pa. The entire process of target irradiation is fully automated. 相似文献
3.
Gianluca Melillo Lorella Izzo Roberto Centore Angela Tuzi Alexander Z. Voskoboynikov Leone Oliva 《Journal of molecular catalysis. A, Chemical》2005,230(1-2):29-33
The meso ansa zirconocene with dimethylsilyl bridge, activated by methylalumoxane, catalyses the ethylene polymerization, producing ethyl-branched polyethylene. With respect to the polymers obtained with the previously investigated meso zirconocenes, we have found higher branching amount and lower molecular weight. The rapid β-H transfer from the growing chain to the coordinated monomer could account for both these features of the polymer. The investigation on the structural parameters of the complex, through X-ray diffraction analysis, and on the electrophilicity of the cationic center, through NMR experiments, suggests, as a possible rationalization of this behavior, the obstruction in the inward site. 相似文献
4.
Pavel S. Kulyabin Georgy P. Goryunov Dmitry Y. Mladentsev Dr. Dmitry V. Uborsky Prof. Dr. Alexander Z. Voskoboynikov Dr. Jo Ann M. Canich Dr. John R. Hagadorn 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(44):10478-10489
Heteroarylamido hafnium post-metallocenes with [C,N,N] ligands were functionalized by the insertion of small electrophilic unsaturated molecules into the CAr−Hf bond of the ligand, which gave rise to various 1,1- and 1,2-insertion complexes with the modified ligands of previously unknown [O,N,N], [N,N,N], [O,N,N,N], and [N,N,N,N] types. It was found that C1 symmetry of the starting complexes, in some cases, results in the formation of two diastereoisomers after 1,1- or 1,2-insertion. Most of the obtained novel complexes were shown to form active catalysts for olefin polymerization in the presence of MAO (methylaluminoxane). Thus, a new approach to the feasible and easy “late stage” modification of the precatalyst structure has been suggested; it can be performed immediately prior to the polymerization tests without isolation and even in a high-throughput manner. 相似文献
5.
A. F. Asachenko V. N. Valaeva V. A. Kudakina D. V. Uborsky V. V. Izmer D. S. Kononovich A. Z. Voskoboynikov 《Russian Chemical Bulletin》2016,65(2):456-463
Nickel catalysts with diazabutadiene ligands promote cross-coupling of benzaldehydes with aryl halides in the presence of zinc as reducing agent, which leads to the corresponding benzhydrols and benzophenones. The benzophenone percentage considerably increases when lithium chloride additive is used. 相似文献
6.
Y. Li Voskoboynikov C.P. Lee S.M. Sze O. Tretyak 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,28(4):475-481
In this article we study the impact of the spin-orbit interaction on the electron quantum confinement for narrow gap semiconductor
quantum dots. The model formulation includes: (1) the effective one-band Hamiltonian approximation; (2) the position- and
energy-dependent quasi-particle effective mass approximation; (3) the finite hard wall confinement potential; and (4) the
spin-dependent Ben Daniel-Duke boundary conditions. The Hartree-Fock approximation is also utilized for evaluating the characteristics
of a two-electron quantum dot system. In our calculation, we describe the spin-orbit interaction which comes from both the
spin-dependent boundary conditions and the Rashba term (for two-electron quantum dot system). It can significantly modify
the electron energy spectrum for InAs semiconductor quantum dots built in the GaAs matrix. The energy state spin-splitting
is strongly dependent on the dot size and reaches an experimentally measurable magnitude for relatively small dots. In addition,
we have found the Coulomb interaction and the spin-splitting are suppressed in quantum dots with small height.
Received 15 May 2001 / Received in final form 14 May 2002 Published online 13 August 2002 相似文献
7.
A. F. Asachenko V. V. Izmer A. V. Babkin I. P. Beletskaya A. Z. Voskoboynikov 《Russian Chemical Bulletin》2008,57(12):2564-2571
A new single-step approach to cyclopenta[a]naphthalenes through TiCl4-catalyzed reactions of 1-trimethylsilyloxycyclopentene with arylacetaldehydes was proposed. 8-Methoxy-5-methyl-2,3-dihydro-1H-cyclopenta[a]naphthalene and its derivatives were studied in oxidation and bromination reactions, as well as in hydrolytic cleavage of
the O-Me bond. 相似文献
8.
C. M.J. Wijers J.-H. Chu O. Voskoboynikov 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,54(2):225-241
The influence of the surrounding semiconducting matrix upon the
optical response of embedded nano-objects (quantum dots) has been
investigated. This system can be described by means of a hybrid model, where the full response is a combination of a macroscopic
electrostatic response term and a dynamic response term, obtained quantum mechanically. The result is a modified discrete
dipole model, where excess discrete dipoles having an excess polarizability with respect to a uniform background identical
to the dielectric host material represent the response. In this model all electrodynamic interactions are screened by the
host material. The electrostatic response is obtained by approximating the quantum dots by embedded dielectric oblate ellipsoids.
Closed expressions for the electrostatic response of these ellipsoids have been derived. The electrodynamic nature of the
dynamic quantum mechanical polarizability term however is unclear. It is not certain whether this polarizability is dressed
or bare. Therefore we have investigated in detail the consequences of both options. Although there is no real qualitative
difference between them, the difference is so large that experiment can easily discriminate between both. Results should be
easily measurable anyhow. 相似文献
9.
In this work, we investigate theoretically the magnetic susceptibility of the three-dimensional cut-torus-shaped quantum rings. The calculations are carried out for the realistic three-dimensional model of InAs/GaAs nano-rings with the hard-wall confinement potential, three-dimensional effective one-electronic-band Hamiltonian with position and energy-dependent effective mass, and Ben Daniel–Duke boundary conditions. This allows us to describe the penetration of the magnetic field into the torus region. At zero temperature, the ring's differential susceptibility demonstrates delta-like paramagnetic peaks, which are generated by aperiodic oscillations of magnetization. With increasing temperature, the peaks gradually transform into Lorenz-shaped peaks and then disappear. As opposed to meso-scopic quantum rings we found a dependence of the peak's amplitude on the dimensions of the rings. 相似文献
10.
[reaction: see text] Vinylation of various azoles (pyrrole, indole, carbazole, and their derivatives) and phenothiazine with vinyl bromides catalyzed by palladium-phosphine complexes results in the respective N-vinylazoles in 30-99% yields. This reaction with cis- and trans-beta-bromostyrenes is stereospecific giving the respective products with full retention of configuration. 相似文献