Low-frequency dynamics of disordered XY spin chains and pinned density waves: from localized spin waves to soliton tunneling

A long-standing problem of the low-energy dynamics of a disordered XY spin chain is re-examined. The case of a rigid chain is studied where the quantum effects can be treated quasiclassically. It is shown that as the frequency decreases, the relevant excitations change from localized spin waves to two-level systems to soliton-antisoliton pairs. The linear-response correlation functions are calculated. The results apply to other periodic glassy systems such as pinned density waves, planar vortex lattices, stripes, and disordered Luttinger liquids.Comment: (v2) Major improvements in presentation style. One figure added (v3) Another minor chang

Radiation-induced hydrogen transfer in metals

The paper presents processes of hydrogen (deuterium) diffusion and release from hydrogen-saturated condensed matters in atomic, molecular and ionized states under the influence of the electron beam and X-ray radiation in the pre-threshold region. The dependence is described between the hydrogen isotope release intensity and the current density and the electron beam energy affecting sample, hydrogen concentration in the material volume and time of radiation exposure to the sample. The energy distribution of the emitted positive ions of hydrogen isotopes is investigated herein. Mechanisms of radiation-induced hydrogen transfer in condensed matters are suggested

Adaptive model of training of students of the direction "Pedagogical education" realization of the polytechnical direction of training in the course of informatics

The article discusses the problem of lack of technical specialists, including in the IT segment, which requires the improvement of both polytechnic training of secondary school students and the meth-odological component of future subject teachers.В статье обсуждается проблема нехватки технических специалистов, в том числе в IT-сегменте, решение которой требует совершенствования как политехнической подготовки учащихся средней школы, так и методической составляющей будущих учителей предметников

Spectroscopic diagnostics of a strongly inhomogeneous optically thick plasma. Part 1. The formation of asymmetric self-reversed emission and absorption lines: determination of electron impact half-width and electron concentration

An analysis has been carried out of the profiles of asymmetrically self-reversed emission lines and of absorption lines using various models for inhomogeneous optically thick plasmas. Conditions of impulsing discharge, exploding wires, sparks, plasma jets, laser ablation of a target, etc. were considered. The possibility of determining electron impact half-width and electron concentration from the wings of asymmetrically self-reversed lines is considered. © 1995 Elsevier B.V. All rights reserved

Spectroscopic diagnostics of a strongly inhomogeneous optically thick plasma. Part 2. Determination of atom concentration and variations of different physical values in the plasma cross-section using asymmetric self-reversed emission and absorption lines

The possibility of determining electron impact half-width and electron concentration, atom concentration and radial distributions of different physical values using the profiles of asymmetric self-reversed emission and absorption lines simultaneously and sequentially recorded over the plasma cross-section is examined. © 1995

PECULIARITIES OF THE DETERMINATION OF THE TEMPERATURE OF A FREELY BURNING ARC DISCHARGE FROM SELF-REVERSED RESONANCE SPECTRAL LINES OF ATOMS.

The results of calculations of the nonuniformity parameter M, used in determining the plasma temperature by Bartels' method, for self-reversed Na I 589. 0/589. 6 nm and Al I 308. 2 nm lines, emitted by an arc discharge burning freely in air, are presented. The calculations were performed for models of the positive column of the arc taking into account the ionization of atoms and the changes in the broadening of the lines in the radial direction. The effect of these factors in calculations of M are discussed