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

Resonant States in High-Temperature Superconductors with Impurities

Z L Kovacevic, Nikolay M. Plakida, R. Hayn

Published Jan 1, 2002• 0 citations
OpenAlex

Abstract

A microscopic theory of resonant states for the Zn-doped CuO_2 plane in superconducting phase is formulated within the effective t-J model. In the model derived from the original p-d model Zn impurities are considered as vacancies for the d states on Cu sites. In the superconducting phase in addition to the local static perturbation induced by the vacancy a dynamical perturbation appears which results in frequency-dependent perturbation matrix. By employing the T-matrix formalism for the Green functions in terms of the Hubbard operators the local density of electronic states with d-, p- and s-symmetry is calculated.

Related papers

Impurity resonant state in d -wave superconductors: In favor of a Kondo-like response

Marijana Kirćan

We investigate the impurity resonant state induced by nonmagnetic impurities in $d$-wave cuprate superconductors in two different impurity models: (i) in a pure potential scattering model within the $T$-matrix approach and (ii) in a Bose--Fermi Kondo model within the large-$\mathcal{N}$ formalism. We modify the superconducting host to resemble the nanoscale electronic inhomogeneities seen in the scanning tunneling microscopy (STM) spectra (i.e., the small-and large-gap domains) and study how this influences the impurity resonance. In the pure potential scattering model, the resonant state is found to be a rather robust feature appearing in all host domains. On the other hand, in the Kondo-like model the impurity resonance can appear in the small-gap regions of the host and be completely suppressed in the large-gap regions; this is in agreement with the STM experimental data for Zn-doped ${\text{Bi}}_{2}{\text{Sr}}_{2}{\text{CaCu}}_{2}{\text{O}}_{8+\ensuremath{\delta}}$. Our results imply that the Kondo spin dynamics of the impurity moment is the origin of the impurity resonant state in $d$-wave superconductors, rather than the pure potential scattering.

arXiv:cond-mat/0702457•Physical Review B•Jun 13, 2008•7 citations

Local spin magnetization around the Zn ion which is doped in the CuO2 plane

Zlata Kovačević

The local static spin susceptibility at neighbor sites from vacant Cu in the CuO 2 plane was obtained. Calculations were performed using one of the variants of the memory function method. Charge-transfer and spin-flip correlation functions were expressed in the framework of the T-matrix formalism in terms of the corresponding Green functions for the ideal t-J model on the square lattice.

Physics of Particles and Nuclei Letters•Sep 1, 2007•0 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

Spectral properties of a quantum impurity ind-wave superconductors

Xi Dai, Ziqiang Wang

The variational approach of Gunnarsson and Sch\"onhammer to the Anderson impurity model is generalized to study d-wave superconductors in the presence of dilute spin-$\frac{1}{2}$ impurities. We show that the local moment is screened when the hybridization exceeds a nonzero critical value at which the ground state changes from a spin doublet to a spin singlet. The electron spectral functions are calculated in both phases. We find that while a Kondo resonance develops above the Fermi level in the singlet phase, the spectral function exhibits a low-energy spectral peak below the Fermi level in the spin-doublet phase. The origin of such a ``virtual Kondo resonance'' is the existence of low-lying collective excitations in the spin-singlet sector. We discuss our results in connection with recent spectroscopic experiments in Zn-doped high-${T}_{c}$ superconductors.

arXiv:cond-mat/0205498•Physical review. B, Condensed matter•May 29, 2003•5 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

Local Moments in Two-Dimensional Quantum Antiferromagnets Doped with Static Vacancies

Debanand Sa

The effect of static impurities in a two-dimensional quantum antiferromagnet has been studied. Creation of a vacancy in an antiferromagnetic lattice yields an impurity Hamiltonian whose x-y part maps to single impurity Anderson model whereas the z-part becomes the X-ray singularity problem. The model is solved where one obtains a bound state giving rise to δ-function density of states. The z-part of the interaction makes this peak asymmetric which follows a power law. It has been argued that the bound state corresponds to a local moment in the system giving rise to Curie-like contribution to the susceptibility. The implications of the present model in the substitutional Zn doped high-T c oxides have been discussed.

International Journal of Modern Physics B•Oct 20, 1998•1 citation
A microscopic theory of resonant states for the Zn-doped CuO_2 plane in superconducting phase is formulated within the effective t-J model. In the model derived from the original p-d model Zn impurities are considered as vacancies for the d states on Cu sites. In the superconducting phase in addition to the local static perturbation induced by the vacancy a dynamical perturbation appears which results in frequency-dependent perturbation matrix. By employing the T-matrix formalism for the Green functions in terms of the Hubbard operators the local density of electronic states with d-, p- and s-symmetry is calculated.
We investigate the impurity resonant state induced by nonmagnetic impurities in ddd-wave cuprate superconductors in two different impurity models: (i) in a pure potential scattering model within the TTT-matrix approach and (ii) in a Bose--Fermi Kondo model within the large-N\mathcal{N}N formalism. We modify the superconducting host to resemble the nanoscale electronic inhomogeneities seen in the scanning tunneling microscopy (STM) spectra (i.e., the small-and large-gap domains) and study how this influences the impurity resonance. In the pure potential scattering model, the resonant state is found to be a rather robust feature appearing in all host domains. On the other hand, in the Kondo-like model the impurity resonance can appear in the small-gap regions of the host and be completely suppressed in the large-gap regions; this is in agreement with the STM experimental data for Zn-doped ${\text{Bi}}_{2}{\text{Sr}}_{2}{\text{CaCu}}_{2}{\text{O}}_{8+\ensuremath{\delta}}$. Our results imply that the Kondo spin dynamics of the impurity moment is the origin of the impurity resonant state in ddd-wave superconductors, rather than the pure potential scattering.
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.
The variational approach of Gunnarsson and Sch\"onhammer to the Anderson impurity model is generalized to study d-wave superconductors in the presence of dilute spin-12\frac{1}{2}21​ impurities. We show that the local moment is screened when the hybridization exceeds a nonzero critical value at which the ground state changes from a spin doublet to a spin singlet. The electron spectral functions are calculated in both phases. We find that while a Kondo resonance develops above the Fermi level in the singlet phase, the spectral function exhibits a low-energy spectral peak below the Fermi level in the spin-doublet phase. The origin of such a ``virtual Kondo resonance'' is the existence of low-lying collective excitations in the spin-singlet sector. We discuss our results in connection with recent spectroscopic experiments in Zn-doped high-Tc{T}_{c}Tc​ superconductors.
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.
The effect of static impurities in a two-dimensional quantum antiferromagnet has been studied. Creation of a vacancy in an antiferromagnetic lattice yields an impurity Hamiltonian whose x-y part maps to single impurity Anderson model whereas the z-part becomes the X-ray singularity problem. The model is solved where one obtains a bound state giving rise to δ-function density of states. The z-part of the interaction makes this peak asymmetric which follows a power law. It has been argued that the bound state corresponds to a local moment in the system giving rise to Curie-like contribution to the susceptibility. The implications of the present model in the substitutional Zn doped high-T c oxides have been discussed.