Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:cond-mat/9510028 · Physical review. B, Condensed matter

Pair breaking by impurities in the two-dimensionalt-Jmodel

José A. Riera, S. Koval, Didier Poilblanc, F. Pantigny

Published Sep 1, 1996• 13 citations
arXivHTMLPDF

Abstract

Pair breaking mechanisms by impurities are investigated in the two-dimensional t-J model by exact diagonalization techniques. Analysis of binding energies and quasiparticle weight of pairs shows that nonmagnetic impurities are more effective in suppressing pairing than magnetic ones in agreement with experimental studies of Zn- and Ni-substituted high-${\mathit{T}}_{\mathit{c}}$ superconductors. Besides, we determine how the localization of holes contributes to the suppression of pairing. Finally, we examine the effect of impurities on the magnetic order by computing the dynamical spin susceptibility. \textcopyright{} 1996 The American Physical Society.

DOI
10.1103/physrevb.54.7441

Related papers

Quasiparticle Properties around a Nonmagnetic Impurity in the Superconducting State of the Two-Dimensionalt-JModel

Hiroki Tsuchiura, Yukio Tanaka, Masao Ogata +1 more

The superconducting state around a well isolated nonmagnetic impurity in the high-Tc superconductors is studied using the two-dimensional t-J model. The spatial dependence of the order parameter and the local density of states are obtained from the numerical diagonalization of the Bogoliubov-de Gennes equation derived using the Gutzwiller approximation. We find a zero-energy peak in the local density of states around the impurity. Different from the previous results on a vortex or surfaces in the t-J model, the splitting of zero-energy peak is not found. The zero-energy states corresponding to the zero-energy peak is approximately localized around the impurity.

arXiv:cond-mat/9906022•Journal of the Physical Society of Japan•Aug 15, 1999•41 citations

Local magnetic moments induced by a nonmagnetic impurity in the two-dimensional t−J model

Satoru Odashima, H. Matsumoto

Local magnetic moments induced by a nonmagnetic impurity in the two-dimensional $t\ensuremath{-}J$ model are investigated by use of a Green function method in a finite-size system (50\ifmmode\times\else\texttimes\fi{}50=2500 sites). Local electron number and nearest-neighbor correlation functions are calculated self-consistently at each lattice point. A local electron number distribution shows that electrons form a bound state around an impurity site and the magnitude of the local moment is enhanced, whereas doped holes can be distributed only apart from the impurity site and destroy an antiferromagnetic spin configuration by their motion. This result is consistent with experimental results of Zn-doped high-${T}_{c}$ superconductors.

Physical review. B, Condensed matter•Jul 1, 1997•16 citations

Zinc Impurities in d -Wave Superconductors

Thomas Maier, Mark Jarrell

We study the two-dimensional Hubbard model with nonmagnetic Zn impurities modeled by binary diagonal disorder using quantum Monte Carlo within the dynamical cluster approximation. With increasing Zn content we find a strong suppression of d-wave superconductivity and an enhancement of antiferromagnetic spin correlations. T(c) vanishes linearly with Zn impurity concentration. The spin susceptibility changes from pseudogap to Curie-Weiss-like behavior indicating the existence of free magnetic moments in the Zn doped system. We interpret these results within the resonating-valence-bond picture.

Physical Review Letters•Jul 26, 2002•9 citations

Zinc Impurities in the 2D Hubbard model

Thomas Maier, Mark Jarrell

We study the two-dimensional Hubbard model with nonmagnetic Zn impurities modeled by binary diagonal disorder using Quantum Monte Carlo within the Dynamical Cluster Approximation. With increasing Zn content we find a strong suppression of d-wave superconductivity concomitant to a reduction of antiferromagnetic spin fluctuations. $T_c$ vanishes linearly with Zn impurity concentration. The spin susceptibility changes from pseudogap to Curie-Weiss like behavior indicating the existence of free magnetic moments in the Zn doped system. We interpret these results within the RVB picture.

arXiv:cond-mat/0201037•Jan 3, 2002•0 citations

Binding of holes to magnetic impurities in a strongly correlated system

Didier Poilblanc, Douglas J. Scalapino, Werner R. Hanke

The effect of a magnetic (S=1/2) impurity coupled to a two-dimensional system of correlated electrons (described by the t-J model) is studied by exact diagonalizations. It is found that, if the exchange coupling of the impurity with the neighboring spins is ferromagnetic or weakly antiferromagnetic, an extra hole can form bound states of different spatial symmetries with the impurity extending to a few lattice spacings. The binding energy is maximum when the impurity is completely decoupled (vacancy) and vanishes for an antiferromagnetic coupling exceeding \ensuremath{\sim}0.3J. Several peaks appear in the single-hole spectral function below the lower edge of the quasiparticle band as signatures of the d-, s-, and p-wave bound states.

arXiv:cond-mat/9404092•Physical review. B, Condensed matter•Nov 1, 1994•27 citations

The effects of Zn impurity on the properties of doped cuprates in the normal state

Yun Song

We study the interplay of quantum impurity, and collective spinon and holon dynamics in Zn doped high-T$_c$ cuprates in the normal state. The two-dimensional t-t$^{\prime}$-J models with one and a small amount of Zn impurity are investigated within a numerical method based on the double-time Green function theory. We study the inhomogeneities of holon density and antiferromagnetic correlation background in cases with different Zn concentrations, and obtain that doped holes tend to assemble around the Zn impurity with their mobility being reduced. Therefore a bound state of holon is formed around the nonmagnetic Zn impurity with the effect helping Zn to introduce local antiferromagnetism around itself. The incommensurate peaks we obtained in the spin structure factor indicate that Zn impurities have effects on mixing the q=($π$, $π$) and q=0 components in spin excitations.

arXiv:cond-mat/0405310•Journal of Physics Condensed Matter•May 14, 2004•0 citations
Pair breaking mechanisms by impurities are investigated in the two-dimensional t-J model by exact diagonalization techniques. Analysis of binding energies and quasiparticle weight of pairs shows that nonmagnetic impurities are more effective in suppressing pairing than magnetic ones in agreement with experimental studies of Zn- and Ni-substituted high-Tc{\mathit{T}}_{\mathit{c}}Tc​ superconductors. Besides, we determine how the localization of holes contributes to the suppression of pairing. Finally, we examine the effect of impurities on the magnetic order by computing the dynamical spin susceptibility. \textcopyright{} 1996 The American Physical Society.
The superconducting state around a well isolated nonmagnetic impurity in the high-Tc superconductors is studied using the two-dimensional t-J model. The spatial dependence of the order parameter and the local density of states are obtained from the numerical diagonalization of the Bogoliubov-de Gennes equation derived using the Gutzwiller approximation. We find a zero-energy peak in the local density of states around the impurity. Different from the previous results on a vortex or surfaces in the t-J model, the splitting of zero-energy peak is not found. The zero-energy states corresponding to the zero-energy peak is approximately localized around the impurity.
Local magnetic moments induced by a nonmagnetic impurity in the two-dimensional $t\ensuremath{-}J$ model are investigated by use of a Green function method in a finite-size system (50\ifmmode\times\else\texttimes\fi{}50=2500 sites). Local electron number and nearest-neighbor correlation functions are calculated self-consistently at each lattice point. A local electron number distribution shows that electrons form a bound state around an impurity site and the magnitude of the local moment is enhanced, whereas doped holes can be distributed only apart from the impurity site and destroy an antiferromagnetic spin configuration by their motion. This result is consistent with experimental results of Zn-doped high-Tc{T}_{c}Tc​ superconductors.
We study the two-dimensional Hubbard model with nonmagnetic Zn impurities modeled by binary diagonal disorder using quantum Monte Carlo within the dynamical cluster approximation. With increasing Zn content we find a strong suppression of d-wave superconductivity and an enhancement of antiferromagnetic spin correlations. T(c) vanishes linearly with Zn impurity concentration. The spin susceptibility changes from pseudogap to Curie-Weiss-like behavior indicating the existence of free magnetic moments in the Zn doped system. We interpret these results within the resonating-valence-bond picture.
We study the two-dimensional Hubbard model with nonmagnetic Zn impurities modeled by binary diagonal disorder using Quantum Monte Carlo within the Dynamical Cluster Approximation. With increasing Zn content we find a strong suppression of d-wave superconductivity concomitant to a reduction of antiferromagnetic spin fluctuations. TcT_cTc​ vanishes linearly with Zn impurity concentration. The spin susceptibility changes from pseudogap to Curie-Weiss like behavior indicating the existence of free magnetic moments in the Zn doped system. We interpret these results within the RVB picture.
The effect of a magnetic (S=1/2) impurity coupled to a two-dimensional system of correlated electrons (described by the t-J model) is studied by exact diagonalizations. It is found that, if the exchange coupling of the impurity with the neighboring spins is ferromagnetic or weakly antiferromagnetic, an extra hole can form bound states of different spatial symmetries with the impurity extending to a few lattice spacings. The binding energy is maximum when the impurity is completely decoupled (vacancy) and vanishes for an antiferromagnetic coupling exceeding \ensuremath{\sim}0.3J. Several peaks appear in the single-hole spectral function below the lower edge of the quasiparticle band as signatures of the d-, s-, and p-wave bound states.
We study the interplay of quantum impurity, and collective spinon and holon dynamics in Zn doped high-Tc_cc​ cuprates in the normal state. The two-dimensional t-t′^{\prime}′-J models with one and a small amount of Zn impurity are investigated within a numerical method based on the double-time Green function theory. We study the inhomogeneities of holon density and antiferromagnetic correlation background in cases with different Zn concentrations, and obtain that doped holes tend to assemble around the Zn impurity with their mobility being reduced. Therefore a bound state of holon is formed around the nonmagnetic Zn impurity with the effect helping Zn to introduce local antiferromagnetism around itself. The incommensurate peaks we obtained in the spin structure factor indicate that Zn impurities have effects on mixing the q=(πππ, πππ) and q=0 components in spin excitations.