Searcharxiv⌕ Search
Home/Archive/arXiv

arXiv · cond-mat/0108286

Double exchange model for RuSr_2(Eu,Gd)Cu_2O_8

H. Aliaga·A. A. Aligia
View original source ↗Read source document ↗Export metadata ↓

Abstract

We propose a double exchange model to describe the RuO_2 planes of RuSr_2(Eu,Gd)Cu_2O_8. The Ru^+5 ions are described by localized spins, and additional electrons provided by the superconducting CuO_2 planes are coupled ferromagnetically to them by Hund rules coupling. We calculate the spin structure factor, magnetic susceptibility and magnetization as a function of magnetic field and temperature, using a Monte Carlo algorithm in which the Ru^+5 spins are treated as classical. Several experiments which seemed in contradiction with one another are explained by the theory.

Explore related subjects

cond-mat

Keep this discovery

BibTeXRIS

H. Aliaga, A. A. Aligia. 2001-09-10. Double exchange model for RuSr_2(Eu,Gd)Cu_2O_8. https://doi.org/10.1016/s0921-4526(02)00613-0

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2015

Spectral Representation for the Effective Macroscopic Response of a Polycrystal: Application to Third-Order Nonlinear Susceptibility

Erratum: In our paper, we show that the spectral representation for isotropic two-component composites also applies to uniaxial polycrystals. We have learned that this result was, in fact, first conjectured by G.W. Milton. While our derivation is more detailed, our result for the spectral function is the same as Milton's. We very much regret not having been aware of this work at the time of writing our paper. Original abstract: We extend the spectral theory used for the calculation of the effective linear response functions of composites to the case of a polycrystalline material with uniaxially anisotropic microscopic symmetry. As an application, we combine these results with a nonlinear decoupling approximation as modified by Ma et al., to calculate the third-order nonlinear optical susceptibility of a uniaxial polycrystal, assuming that the effective dielectric function of the polycrystal can be calculated within the effective-medium approximation.

cond-mat↗
arXiv2014

Towards quantum well hot hole lasers

It should be possible to improve hot-hole laser performance by moving from bulk materials to a quantum well structure. The extra design parameters enable us to alter the band structure by changing the crystal orientation of the growth direction; to use the well width to shift the subband offsets, enabling the effect of the LO phonon scattering cut-off to be controlled; and to use modulation doping to ensure a high hole concentration to increase the gain without the dopants being present in the gain region. We present the first simulations of THz quantum well hot-hole lasers that can produce inversion and optical gain.

cond-mat↗