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Title: Linear response theory and the universal nature of the magnetic excitation spectrum of the cuprates

Abstract

Linear response theory, commonly known as the random-phase approximation (RPA), predicts a rich magnetic excitation spectrum for d-wave superconductors. Many of the features predicted by such calculations appear to be reflected in inelastic neutron-scattering data of the cuprates. In this paper, I will present results from RPA calculations whose input is based on angle-resolved photoemission data, and discuss possible relevance to inelastic neutron-scattering data of La{sub 2-x}Sr{sub x}CuO{sub 4} (LSCO), YBa{sub 2}Cu{sub 3}O{sub 6+x} (YBCO), and Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+x} (Bi2212) in their superconducting and nonsuperconducting phases. In particular, the question of the universality of the magnetic excitation spectrum will be addressed.

Authors:
 [1]
  1. Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)
Publication Date:
OSTI Identifier:
20951420
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 18; Other Information: DOI: 10.1103/PhysRevB.75.184514; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 36 MATERIALS SCIENCE; BARIUM OXIDES; BISMUTH OXIDES; CALCIUM OXIDES; COPPER OXIDES; CUPRATES; D WAVES; EXCITATION; HIGH-TC SUPERCONDUCTORS; INELASTIC SCATTERING; LANTHANUM COMPOUNDS; NEUTRON DIFFRACTION; NEUTRON REACTIONS; PHOTOELECTRON SPECTROSCOPY; PHOTOEMISSION; RANDOM PHASE APPROXIMATION; SPECTRA; STRONTIUM OXIDES; SUPERCONDUCTIVITY; YTTRIUM OXIDES

Citation Formats

Norman, M. R. Linear response theory and the universal nature of the magnetic excitation spectrum of the cuprates. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.184514.
Norman, M. R. Linear response theory and the universal nature of the magnetic excitation spectrum of the cuprates. United States. doi:10.1103/PHYSREVB.75.184514.
Norman, M. R. Tue . "Linear response theory and the universal nature of the magnetic excitation spectrum of the cuprates". United States. doi:10.1103/PHYSREVB.75.184514.
@article{osti_20951420,
title = {Linear response theory and the universal nature of the magnetic excitation spectrum of the cuprates},
author = {Norman, M. R.},
abstractNote = {Linear response theory, commonly known as the random-phase approximation (RPA), predicts a rich magnetic excitation spectrum for d-wave superconductors. Many of the features predicted by such calculations appear to be reflected in inelastic neutron-scattering data of the cuprates. In this paper, I will present results from RPA calculations whose input is based on angle-resolved photoemission data, and discuss possible relevance to inelastic neutron-scattering data of La{sub 2-x}Sr{sub x}CuO{sub 4} (LSCO), YBa{sub 2}Cu{sub 3}O{sub 6+x} (YBCO), and Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+x} (Bi2212) in their superconducting and nonsuperconducting phases. In particular, the question of the universality of the magnetic excitation spectrum will be addressed.},
doi = {10.1103/PHYSREVB.75.184514},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 18,
volume = 75,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}
  • Linear response theory, commonly known as the random-phase approximation (RPA), predicts a rich magnetic excitation spectrum for d-wave superconductors. Many of the features predicted by such calculations appear to be reflected in inelastic neutron-scattering data of the cuprates. In this paper, I will present results from RPA calculations whose input is based on angle-resolved photoemission data, and discuss possible relevance to inelastic neutron-scattering data of La{sub 2-x}Sr{sub x}CuO{sub 4} (LSCO), YBa{sub 2}Cu{sub 3}O{sub 6+x} (YBCO), and Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+x} (Bi2212) in their superconducting and nonsuperconducting phases. In particular, the question of the universality of the magnetic excitation spectrummore » will be addressed.« less
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  • Recent experiments have addressed the nature of the charge order seen in underdoped cuprates. In this paper, I show that x-ray absorption and linear dichroism are excellent probes of such order. Ab initio calculations reveal that a d-wave charge density wave order involving the oxygen ions is a much better description of the data than alternate models.
  • A new implementation of the approximate coupled cluster singles and doubles CC2 linear response model is reported. It employs a Cholesky decomposition of the two-electron integrals that significantly reduces the computational cost and the storage requirements of the method compared to standard implementations. Our algorithm also exploits a partitioning form of the CC2 equations which reduces the dimension of the problem and avoids the storage of doubles amplitudes. We present calculation of excitation energies of benzene using a hierarchy of basis sets and compare the results with conventional CC2 calculations. The reduction of the scaling is evaluated as well asmore » the effect of the Cholesky decomposition parameter on the quality of the results. The new algorithm is used to perform an extrapolation to complete basis set investigation on the spectroscopically interesting benzylallene conformers. A set of calculations on medium-sized molecules is carried out to check the dependence of the accuracy of the results on the decomposition thresholds. Moreover, CC2 singlet excitation energies of the free base porphin are also presented.« less