Suppression of indirect exchange and symmetry breaking in the antiferromagnetic metal HoB12 with dynamic charge stripes
Precise angle-resolved magnetoresistance (ARM) measurements are applied to reveal the origin of symmetry
lowering in electron transport and the emergence of a huge number of magnetic phases in the ground state of the
antiferromagnetic metal HoB12 with fcc crystal structure. By analyzing the polar H-θ-ϕ magnetic phase diagrams
of this compound reconstructed from the experimental ARM data, we argue that nonequilibrium electron density
oscillations (dynamic charge stripes) are responsible for the suppression of the indirect Ruderman-Kittel-Kasuya-
Yosida exchange along the <110> directions between the nearest neighboring magnetic moments of Ho3+ ions in
this strongly correlated electron system.
We consider magnetic oscillations of resistivity of a clean (mean free path ) hollow cylinder with fluctuating (with an amplitude of fluctuations ) radius R, threaded by magnetic flux Φ. We demonstrate, that for weak fluctuations () the oscillations have a standard period 2Φ0, characteristic for oscillations in a clean system, while for they become Φ0-periodic, which was expected only for dirty systems with . The work is motivated by observation of predominantly Φ0-periodic magnetic oscillations in very clean Bismuth wires.
We study the diffusive electron-electron interaction correction to conductivity by analyzing simultaneously ρxx and ρxy for disordered 2D electron systems in Si in a tilted magnetic field. Tilting the field is shown to be a straightforward tool to disentangle spin and orbital effects. In particular, by changing the tilt angle we prove experimentally that in the field range gμBB>kBT the correction depends on the modulus of the magnetic field rather than on its direction, which is expected for a system with isotropic g factor. In the high-field limit, the correction behaves as ln(B), as expected theoretically [Lee and Ramakrishnan, Phys. Rev. B 26, 4009 (1982)]. Our data prove that the diffusive electron-electron interaction correction to conductivity is not solely responsible for the huge and temperature-dependent magnetoresistance in a parallel field, typically observed in Si-MOSFETs.
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.
This volume presents new results in the study and optimization of information transmission models in telecommunication networks using different approaches, mainly based on theiries of queueing systems and queueing networks .
The paper provides a number of proposed draft operational guidelines for technology measurement and includes a number of tentative technology definitions to be used for statistical purposes, principles for identification and classification of potentially growing technology areas, suggestions on the survey strategies and indicators. These are the key components of an internationally harmonized framework for collecting and interpreting technology data that would need to be further developed through a broader consultation process. A summary of definitions of technology already available in OECD manuals and the stocktaking results are provided in the Annex section.