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Title: One-Particle Spectral Function and Local Density of States in a Phenomenological Mixed-Phase Model for High-Temperature Superconductors

Abstract

The dynamical properties of a recently introduced phenomenological model for high-temperature superconductors are investigated. In the clean limit, it was observed that none of the homogeneous or striped states that are induced by the model at low temperatures can reproduce the recent angle-resolved photoemission results for La{sub 2-x}Sr{sub x}CuO{sub 4} [Yoshida et al., Phys. Rev. Lett. 91, 027001 (2003)], which show a signal with two branches in the underdoped regime. On the other hand, upon including quenched disorder in the model and breaking the homogeneous state into 'patches' that are locally either superconducting or antiferromagnetic, the two-branch spectra can be reproduced. In this picture, the nodal regions are caused by d-wave superconducting clusters. Studying the density of states (DOS), a pseudogap is observed, caused by the mixture of the gapped antiferromagnetic state and a d-wave superconductor. The local DOS can be interpreted using a mixed-phase picture, similar to what is observed in tunneling experiments. It is concluded that a simple phenomenological model for cuprates can capture several of the one-particle features observed in the underdoped regime of these materials.

Authors:
 [1];  [2];  [2];  [2]
  1. Max-Planck-Institut fur Feskorperforschung, Stuttgart, Germany
  2. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1003456
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review B; Journal Volume: 73; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CUPRATES; MIXTURES; PHOTOEMISSION; SPECTRA; SPECTRAL FUNCTIONS; SUPERCONDUCTORS; TUNNELING; Spectral; One-particle; high-temperature; superconductors

Citation Formats

Mayr, Matthias, Alvarez, Gonzalo, Moreo, Adriana, and Dagotto, Elbio R. One-Particle Spectral Function and Local Density of States in a Phenomenological Mixed-Phase Model for High-Temperature Superconductors. United States: N. p., 2006. Web. doi:10.1103/PhysRevB.73.014509.
Mayr, Matthias, Alvarez, Gonzalo, Moreo, Adriana, & Dagotto, Elbio R. One-Particle Spectral Function and Local Density of States in a Phenomenological Mixed-Phase Model for High-Temperature Superconductors. United States. doi:10.1103/PhysRevB.73.014509.
Mayr, Matthias, Alvarez, Gonzalo, Moreo, Adriana, and Dagotto, Elbio R. Sun . "One-Particle Spectral Function and Local Density of States in a Phenomenological Mixed-Phase Model for High-Temperature Superconductors". United States. doi:10.1103/PhysRevB.73.014509.
@article{osti_1003456,
title = {One-Particle Spectral Function and Local Density of States in a Phenomenological Mixed-Phase Model for High-Temperature Superconductors},
author = {Mayr, Matthias and Alvarez, Gonzalo and Moreo, Adriana and Dagotto, Elbio R},
abstractNote = {The dynamical properties of a recently introduced phenomenological model for high-temperature superconductors are investigated. In the clean limit, it was observed that none of the homogeneous or striped states that are induced by the model at low temperatures can reproduce the recent angle-resolved photoemission results for La{sub 2-x}Sr{sub x}CuO{sub 4} [Yoshida et al., Phys. Rev. Lett. 91, 027001 (2003)], which show a signal with two branches in the underdoped regime. On the other hand, upon including quenched disorder in the model and breaking the homogeneous state into 'patches' that are locally either superconducting or antiferromagnetic, the two-branch spectra can be reproduced. In this picture, the nodal regions are caused by d-wave superconducting clusters. Studying the density of states (DOS), a pseudogap is observed, caused by the mixture of the gapped antiferromagnetic state and a d-wave superconductor. The local DOS can be interpreted using a mixed-phase picture, similar to what is observed in tunneling experiments. It is concluded that a simple phenomenological model for cuprates can capture several of the one-particle features observed in the underdoped regime of these materials.},
doi = {10.1103/PhysRevB.73.014509},
journal = {Physical Review B},
number = 1,
volume = 73,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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