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Title: Spectral properties of waves in superlattices with 2D and 3D inhomogeneities

Abstract

We investigate the dynamic susceptibility and one-dimensional density of states in an initially sinusoidal superlattice containing simultaneously 2D phase inhomogeneities simulating correlated rough-nesses of superlattice interfaces and 3D amplitude inhomogeneities of the superlattice layer materials. The analytic expression for the averaged Green's function of the sinusoidal superlattice with two phase inhomogeneities is derived in the Bourret approximation. It is shown that the effect of increasing asymmetry in the peak heights of dynamic susceptibility at the Brillouin zone boundary of the superlattice, which was discovered earlier [15] upon an increase in root-mean-square (rms) fluctuations, also takes place upon an increase in the correlation wavenumber of inhomogeneities. However, the peaks in this case also become closer, and the width and depth of the gap in the density of states decrease thereby. It is shown that the enhancement of rms fluctuations of 3D amplitude inhomogeneities in a superlattice containing 2D phase inhomogeneities suppresses the effect of dynamic susceptibility asymmetry and leads to a slight broadening of the gap in the density of states and a decrease in its depth. Targeted experiments aimed at detecting the effects studied here would facilitate the development of radio-spectroscopic and optical methods for identifying the presence of inhomogeneitiesmore » of various dimensions in multilayer magnetic and optical structures.« less

Authors:
;  [1]
  1. Russian Academy of Sciences, L.V. Kirensky Institute of Physics, Siberian Branch (Russian Federation)
Publication Date:
OSTI Identifier:
22028041
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Experimental and Theoretical Physics; Journal Volume: 113; Journal Issue: 2; Other Information: Copyright (c) 2011 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AMPLITUDES; APPROXIMATIONS; ASYMMETRY; BRILLOUIN ZONES; CORRELATIONS; ENERGY GAP; ENERGY-LEVEL DENSITY; FLUCTUATIONS; GREEN FUNCTION; INTERFACES; LAYERS; MAGNETIC MATERIALS; SUPERLATTICES

Citation Formats

Ignatchenko, V. A., E-mail: vignatch@iph.krasn.ru, and Tsikalov, D. S. Spectral properties of waves in superlattices with 2D and 3D inhomogeneities. United States: N. p., 2011. Web. doi:10.1134/S1063776111080061.
Ignatchenko, V. A., E-mail: vignatch@iph.krasn.ru, & Tsikalov, D. S. Spectral properties of waves in superlattices with 2D and 3D inhomogeneities. United States. doi:10.1134/S1063776111080061.
Ignatchenko, V. A., E-mail: vignatch@iph.krasn.ru, and Tsikalov, D. S. Mon . "Spectral properties of waves in superlattices with 2D and 3D inhomogeneities". United States. doi:10.1134/S1063776111080061.
@article{osti_22028041,
title = {Spectral properties of waves in superlattices with 2D and 3D inhomogeneities},
author = {Ignatchenko, V. A., E-mail: vignatch@iph.krasn.ru and Tsikalov, D. S.},
abstractNote = {We investigate the dynamic susceptibility and one-dimensional density of states in an initially sinusoidal superlattice containing simultaneously 2D phase inhomogeneities simulating correlated rough-nesses of superlattice interfaces and 3D amplitude inhomogeneities of the superlattice layer materials. The analytic expression for the averaged Green's function of the sinusoidal superlattice with two phase inhomogeneities is derived in the Bourret approximation. It is shown that the effect of increasing asymmetry in the peak heights of dynamic susceptibility at the Brillouin zone boundary of the superlattice, which was discovered earlier [15] upon an increase in root-mean-square (rms) fluctuations, also takes place upon an increase in the correlation wavenumber of inhomogeneities. However, the peaks in this case also become closer, and the width and depth of the gap in the density of states decrease thereby. It is shown that the enhancement of rms fluctuations of 3D amplitude inhomogeneities in a superlattice containing 2D phase inhomogeneities suppresses the effect of dynamic susceptibility asymmetry and leads to a slight broadening of the gap in the density of states and a decrease in its depth. Targeted experiments aimed at detecting the effects studied here would facilitate the development of radio-spectroscopic and optical methods for identifying the presence of inhomogeneities of various dimensions in multilayer magnetic and optical structures.},
doi = {10.1134/S1063776111080061},
journal = {Journal of Experimental and Theoretical Physics},
number = 2,
volume = 113,
place = {United States},
year = {Mon Aug 15 00:00:00 EDT 2011},
month = {Mon Aug 15 00:00:00 EDT 2011}
}
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  • A novel copper-azido coordination polymer, [Cu{sub 2}(N{sub 3}){sub 3}(L)]{sub n} (1, HL=pyrazine-2-carboxylic acid), has been synthesized by hydrothermal reaction with 'Non-innocent' reagent in the aqueous solution. In the reaction system, Cu{sup II} ions are avoided to reduce to Cu{sup I} ions due to the existence of Nd{sup III}. It is found that the complex is a 3D structure based on two double EO azido bridged trimmers and octahedron Cu{sup II} ions, in which the azide ligands take on EO and {mu}{sub 1,1,3} mode to form Cu{sup II}-azido 2D layers, furthermore L ligands pillar 2D layers into an infinite 3D frameworkmore » with the Schlaefli symbol of {l_brace}4;6{sup 2}{r_brace}4{l_brace}4{sup 2};6{sup 12};8{sup 10};10{sup 4}{r_brace}{l_brace}4{sup 2};6{sup 4}{r_brace}. Magnetic studies revealed that the interactions between the Cu{sup II} ions in the trimmer are ferromagnetic for the Cu-N-Cu angle nearly 98 Degree-Sign , while the interactions between the trimmer and octahedron Cu{sup II} ion are antiferromgantic and result in an antiferromagnetic state. - Graphical abstract: A 3D complex containing novel 2D Cu{sup II}-azido layers, [Cu{sub 2}(N{sub 3}){sub 3}(L)]{sub n} (HL=pyrazine-2-carboxylic acid), was synthesized by hydrothermal reaction and exhibit interesting structure and magnetic properties. Highlights: Black-Right-Pointing-Pointer 'Non-innocent' reagents plays a key role in the process of formation of this complex. Black-Right-Pointing-Pointer 2D layer is formed only by Cu{sup II} ions and azido ligands. Black-Right-Pointing-Pointer Pyrazine-2-carboxylate ligands reinforce 2D layers and pillar them into an infinite 3D framework. Black-Right-Pointing-Pointer Magnetic study indicates that alternating FM-AF coupling exists in the complex.« less