OneParticle Spectral Function and Local Density of States in a Phenomenological MixedPhase Model for HighTemperature Superconductors
Abstract
The dynamical properties of a recently introduced phenomenological model for hightemperature 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 angleresolved photoemission results for La{sub 2x}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 twobranch spectra can be reproduced. In this picture, the nodal regions are caused by dwave superconducting clusters. Studying the density of states (DOS), a pseudogap is observed, caused by the mixture of the gapped antiferromagnetic state and a dwave superconductor. The local DOS can be interpreted using a mixedphase picture, similar to what is observed in tunneling experiments. It is concluded that a simple phenomenological model for cuprates can capture several of the oneparticle features observed in the underdoped regime of these materials.
 Authors:
 MaxPlanckInstitut fur Feskorperforschung, Stuttgart, Germany
 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:
 DEAC0500OR22725
 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; Oneparticle; hightemperature; superconductors
Citation Formats
Mayr, Matthias, Alvarez, Gonzalo, Moreo, Adriana, and Dagotto, Elbio R. OneParticle Spectral Function and Local Density of States in a Phenomenological MixedPhase Model for HighTemperature Superconductors. United States: N. p., 2006.
Web. doi:10.1103/PhysRevB.73.014509.
Mayr, Matthias, Alvarez, Gonzalo, Moreo, Adriana, & Dagotto, Elbio R. OneParticle Spectral Function and Local Density of States in a Phenomenological MixedPhase Model for HighTemperature Superconductors. United States. doi:10.1103/PhysRevB.73.014509.
Mayr, Matthias, Alvarez, Gonzalo, Moreo, Adriana, and Dagotto, Elbio R. Sun .
"OneParticle Spectral Function and Local Density of States in a Phenomenological MixedPhase Model for HighTemperature Superconductors". United States.
doi:10.1103/PhysRevB.73.014509.
@article{osti_1003456,
title = {OneParticle Spectral Function and Local Density of States in a Phenomenological MixedPhase Model for HighTemperature 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 hightemperature 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 angleresolved photoemission results for La{sub 2x}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 twobranch spectra can be reproduced. In this picture, the nodal regions are caused by dwave superconducting clusters. Studying the density of states (DOS), a pseudogap is observed, caused by the mixture of the gapped antiferromagnetic state and a dwave superconductor. The local DOS can be interpreted using a mixedphase picture, similar to what is observed in tunneling experiments. It is concluded that a simple phenomenological model for cuprates can capture several of the oneparticle 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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