Signatures of pairing in the magnetic excitation spectrum of strongly correlated twoleg ladders [Signatures of pairing in the magnetic excitation spectrum of strongly correlated ladders]
Abstract
Magnetic interactions are widely believed to play a crucial role in the microscopic mechanism leading to high critical temperature superconductivity. It is therefore important to study the signatures of pairing in the magnetic excitation spectrum of simple models known to show unconventional superconducting tendencies. Using the density matrix renormalization group technique, we calculate the dynamical spin structure factor S(k,ω) of a generalized t–U–J Hubbard model away from half filling in a twoleg ladder geometry. The addition of J enhances pairing tendencies. We analyze quantitatively the signatures of pairing in the magnetic excitation spectra. We found that the superconducting paircorrelation strength, that can be estimated independently from ground state properties, is closely correlated with the integrated lowenergy magnetic spectral weight in the vicinity of (π,π). In this wavevector region, robust spin incommensurate features develop with increasing doping. The branch of the spectrum with rung direction wave vector k _{rung}=0 does not change substantially with doping where pairing dominates and thus plays a minor role. As a result, we discuss the implications of our results for neutron scattering experiments, where the spin excitation dynamics of holedoped quasionedimensional magnetic materials can be measured and also address implications for recent resonant inelastic xray scatteringmore »
 Authors:
 The Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Publication Date:
 Research Org.:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC22)
 OSTI Identifier:
 1413613
 Alternate Identifier(s):
 OSTI ID: 1408556
 Grant/Contract Number:
 AC0500OR22725
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Physical Review B
 Additional Journal Information:
 Journal Volume: 96; Journal Issue: 20; Journal ID: ISSN 24699950
 Publisher:
 American Physical Society (APS)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY
Citation Formats
Nocera, Alberto, Patel, Niravkumar D., Dagotto, Elbio R., and Alvarez, Gonzalo. Signatures of pairing in the magnetic excitation spectrum of strongly correlated twoleg ladders [Signatures of pairing in the magnetic excitation spectrum of strongly correlated ladders]. United States: N. p., 2017.
Web. doi:10.1103/PhysRevB.96.205120.
Nocera, Alberto, Patel, Niravkumar D., Dagotto, Elbio R., & Alvarez, Gonzalo. Signatures of pairing in the magnetic excitation spectrum of strongly correlated twoleg ladders [Signatures of pairing in the magnetic excitation spectrum of strongly correlated ladders]. United States. doi:10.1103/PhysRevB.96.205120.
Nocera, Alberto, Patel, Niravkumar D., Dagotto, Elbio R., and Alvarez, Gonzalo. 2017.
"Signatures of pairing in the magnetic excitation spectrum of strongly correlated twoleg ladders [Signatures of pairing in the magnetic excitation spectrum of strongly correlated ladders]". United States.
doi:10.1103/PhysRevB.96.205120.
@article{osti_1413613,
title = {Signatures of pairing in the magnetic excitation spectrum of strongly correlated twoleg ladders [Signatures of pairing in the magnetic excitation spectrum of strongly correlated ladders]},
author = {Nocera, Alberto and Patel, Niravkumar D. and Dagotto, Elbio R. and Alvarez, Gonzalo},
abstractNote = {Magnetic interactions are widely believed to play a crucial role in the microscopic mechanism leading to high critical temperature superconductivity. It is therefore important to study the signatures of pairing in the magnetic excitation spectrum of simple models known to show unconventional superconducting tendencies. Using the density matrix renormalization group technique, we calculate the dynamical spin structure factor S(k,ω) of a generalized t–U–J Hubbard model away from half filling in a twoleg ladder geometry. The addition of J enhances pairing tendencies. We analyze quantitatively the signatures of pairing in the magnetic excitation spectra. We found that the superconducting paircorrelation strength, that can be estimated independently from ground state properties, is closely correlated with the integrated lowenergy magnetic spectral weight in the vicinity of (π,π). In this wavevector region, robust spin incommensurate features develop with increasing doping. The branch of the spectrum with rung direction wave vector krung=0 does not change substantially with doping where pairing dominates and thus plays a minor role. As a result, we discuss the implications of our results for neutron scattering experiments, where the spin excitation dynamics of holedoped quasionedimensional magnetic materials can be measured and also address implications for recent resonant inelastic xray scattering experiments.},
doi = {10.1103/PhysRevB.96.205120},
journal = {Physical Review B},
number = 20,
volume = 96,
place = {United States},
year = 2017,
month =
}

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