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21.
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We study the effects of the RKKY interaction between magnetic impurities on the mesoscopic conductance fluctuations of a metal ring with dilute magnetic impurities. At sufficiently low temperatures and strong magnetic fields, the loss of electron coherence occurs mainly due to the scattering off rare pairs of strongly coupled magnetic impurities. We establish a relation between the dephasing rate and the distribution function of the exchange interaction within such pairs. In the case of the RKKY exchange interaction, this rate exhibits 1/B(2) behavior in strong magnetic fields. We demonstrate that the Aharonov-Bohm conductance oscillations may be used as a probe of the distribution function of the exchange interaction between magnetic impurities in metals.  相似文献   
23.
The paper is devoted to applying the confinement mechanism proposed earlier by one of the authors to estimate the possible parameters of the confining SU(3)-gluonic field in vector ?-meson. The estimates obtained are consistent with the leptonic widths of the given meson. The corresponding estimates of the gluon concentrations, electric and magnetic colour field strengths are also adduced for the mentioned field at the scales of the meson under consideration.  相似文献   
24.
Optical and magneto-optical properties of three-dimensional magnetic photonic crystals, based on magnetite Fe3O4 embedded into an opal film matrix, are investigated in both transmission and reflection. A strong enhancement of the polar Kerr effect and a modification of the Faraday effect have been found near the photonic band-gap of about 1.8 eV. Unusual changes of hysteresis curves and their dependence on photon energy have been revealed in the spectral region where the magneto-optical effect reverses its sign. This phenomenon has been explained by two types of magnetite particles inside the opal matrix having different coercive fields and spectral behaviour.  相似文献   
25.
Nekrasov  I. A.  Pavlov  N. S.  Sadovskii  M. V. 《JETP Letters》2019,109(5):345-345
JETP Letters - The name of the second author should read N. S. Pavlov  相似文献   
26.
It is shown that (Ga,Mn)As layers formed by Mn+ ion implantation into GaAs and subsequent annealing by an excimer laser pulse with an energy density to 200–300 mJ/cm2 feature the properties of the p-type semiconductor and ferromagnetic properties. The threshold dose of implanted ions (~1015 cm–2) for activating Mn acceptors is determined. The sheet hole concentration and the Curie temperature increase with further increasing Mn+ ion dose. Hysteresis loops in the magnetic field dependences of the Hall effect, the negative magnetoresistance, and magnetic and structural studies suggest that the layers are analogues of single-phase ferromagnetic compounds (Ga,Mn)As formed by low-temperature molecular beam epitaxy.  相似文献   
27.
Abashin M  Levy U  Ikeda K  Fainman Y 《Optics letters》2007,32(17):2602-2604
We study the effects of metal-coated fiber near-field probes on the performance of nanophotonic devices. Employing a heterodyne near-field scanning optical microscope and analyzing transmission characteristics, we find that a metal-coated probe can typically introduce a 3 dB intensity loss and a 0.2 rad phase shift during characterization of a straight waveguide made in a silicon-on-insulator system. In resonant nanophotonic structures such as a 5 mum radius microring resonator, we demonstrate that the probe induces a 1 nm shift in resonant wavelength and decreases the resonator quality factor, Q, from 1100 to 480.  相似文献   
28.
29.
The algebro-geometric approach for integrability of semi-Hamiltonian hydrodynamic type systems is presented. The class of symmetric hydrodynamic type systems is defined and the calculation of the associated Riemann surfaces is greatly simplified for this class. Many interesting and physically motivated examples are investigated.  相似文献   
30.
Scattering of particles in the gravitational field of rotating black holes is considered. It is shown that scattering energy of particles in the centre of mass system can obtain very large values not only for extremal black holes but also for nonextremal ones. Extraction of energy after the collision is investigated. It is shown that due to the Penrose process the energy of the particle escaping the hole at infinity can be large. Contradictions in the problem of getting high energetic particles escaping the black hole are resolved.  相似文献   
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