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/9606144 · Physical review. B, Condensed matter

Photoemission spectra in t−J ladders with two legs

Stephan Haas, Elbio R. Dagotto

Published Aug 1, 1996• 20 citations
arXivHTMLPDF

Abstract

Photoemission spectra for the isotropic two-leg $t\ensuremath{-}J$ ladder are calculated at various hole-doping levels using exact diagonalization techniques. Low-energy sharp features caused by short-range antiferromagnetic correlations are observed at finite doping levels close to half-filling, above the naive Fermi momentum. These features should be observable in angle-resolved photoemission experiments. In addition, the formation of a $d$-wave pairing condensate as the ratio $\frac{J}{t}$ is increased leads to dynamically generated spectral weight for momenta close to ${k}_{F}$ where the ${d}_{{x}^{2}\ensuremath{-}{y}^{2}}$ order parameter is large.

DOI
10.1103/physrevb.54.r3718

Related papers

Hole-density evolution of the one-particle spectral function in doped ladders

George Balster Martins, C. J. Gazza, Elbio R. Dagotto

The spectral function $A(\mathbf{q},\ensuremath{\omega})$ of doped $t\ensuremath{-}J$ ladders is presented on clusters with up to $2\ifmmode\times\else\texttimes\fi{}20$ sites at zero temperature applying a recently developed technique that uses up to $\ensuremath{\sim}6\ifmmode\times\else\texttimes\fi{}{10}^{6}$ rung-basis states. Similarities with photoemission results for the two-dimensional cuprates are observed, such as the existence of a gap at $(\ensuremath{\pi},0)$ near half-filling (caused by hole pair formation) and flat bands in its vicinity. These features should be observable in angle-resolved photoemission spectroscopy experiments on ladders. The main result of the paper is the nontrivial evolution of the spectral function from a narrow band at $x=0$, to a quasinoninteracting band at $x>~0.5$. It was also observed that the low-energy peaks of a cluster spectra acquire finite linewidths as their energies move away from the chemical potential.

arXiv:cond-mat/9901054•Physical review. B, Condensed matter•Jun 1, 1999•11 citations

Properties of lightly dopedt-Jtwo-leg ladders

Matthias Troyer, Hirokazu Tsunetsugu, Thomas Maurice Rice

We have numerically investigated the doped t-J ladder using exact diagonalization. We have studied both the limit of strong interchain coupling and isotropic coupling. The ladder scales to the Luther-Emery liquid regime in the strong interchain coupling limit. In this strong coupling limit there is a simple picture of the excitation spectrum that can be continued to explain the behavior at isotropic coupling. At J=0 we have indications of a ferromagnetic ground state. At a large J/t the ladder is phase separated into holes and a Heisenberg ladder. At intermediate coupling the ground state shows hole pairing with a modified d-wave symmetry. The excitation spectrum separates into a limited number of quasiparticles which carry charge +\ensuremath{\Vert}e\ensuremath{\Vert} and spin 1/2 and a triplet magnon mode. At half filling the former vanish but the latter evolves continuously into the magnon band of the spin liquid. At low doping the quasiparticles form a dilute Fermi gas with a strong attraction but simultaneously the Fermi wave vector, as would be measured in photoemission, is large. The dynamical structure factors are calculated and are found to be very similar to calculations on two-dimensional clusters. \textcopyright{} 1996 The American Physical Society.

arXiv:cond-mat/9510150•Physical review. B, Condensed matter•Jan 1, 1996•173 citations

Signatures of pairing in the magnetic excitation spectrum of strongly correlated two-leg ladders

Alberto Nocera, N. D. Patel, Elbio R. Dagotto +1 more

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 $S(\mathbf{k},\ensuremath{\omega})$ of a generalized $t\ensuremath{-}U\ensuremath{-}J$ Hubbard model away from half filling in a two-leg 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 pair-correlation strength, that can be estimated independently from ground state properties, is closely correlated with the integrated low-energy magnetic spectral weight in the vicinity of $(\ensuremath{\pi},\ensuremath{\pi})$. In this wave-vector region, robust spin incommensurate features develop with increasing doping. The branch of the spectrum with rung direction wave vector ${k}_{\mathrm{rung}}=0$ does not change substantially with doping where pairing dominates and thus plays a minor role. We discuss the implications of our results for neutron scattering experiments, where the spin excitation dynamics of hole-doped quasi-one-dimensional magnetic materials can be measured and also address implications for recent resonant inelastic x-ray scattering experiments.

arXiv:1707.02626•Physical review. B./Physical review. B•Nov 13, 2017•14 citations

Signatures of Pairing in the Magnetic Excitation Spectrum of Strongly Correlated two-leg Ladders

Alberto Nocera, Nirav Patel, Elbio R. Dagotto +1 more

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 $S(\mathbf{k},\ensuremath{\omega})$ of a generalized $t\ensuremath{-}U\ensuremath{-}J$ Hubbard model away from half filling in a two-leg 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 pair-correlation strength, that can be estimated independently from ground state properties, is closely correlated with the integrated low-energy magnetic spectral weight in the vicinity of $(\ensuremath{\pi},\ensuremath{\pi})$. In this wave-vector region, robust spin incommensurate features develop with increasing doping. The branch of the spectrum with rung direction wave vector ${k}_{\mathrm{rung}}=0$ does not change substantially with doping where pairing dominates and thus plays a minor role. We discuss the implications of our results for neutron scattering experiments, where the spin excitation dynamics of hole-doped quasi-one-dimensional magnetic materials can be measured and also address implications for recent resonant inelastic x-ray scattering experiments.

Bulletin of the American Physical Society•Mar 7, 2018•0 citations

Monte Carlo study of the pairing interaction in the two-leg Hubbard ladder

Bulut, N., T. Dahm, Douglas J. Scalapino

Monte Carlo calculations of the irreducible particle-particle interaction on a two-leg Hubbard ladder doped near half-filling are reported. As the temperature is lowered, this interaction develops structure in momentum space similar to the magnetic susceptibility $χ(q)$ and reflects the development of strong short-range antiferromagnetic correlations. Using this interaction, the eigenfunction of the leading singlet pair eigenvalue is found to have $d_{x^2-y^2}$ like symmetry. The single-particle spectral weight is also shown to peak near $(π,0)$ and $(0,π)$ when the ratio of the inter- to intra-chain hopping $t_{\perp}/t\simeq 1.5$, leading to an increased tendency for pairing.

arXiv:cond-mat/9612166•Dec 18, 1996•0 citations

Quasiparticle dispersion of thet-Jand Hubbard models

Adriana Moreo, Stephan Haas, Anders W. Sandvik +1 more

The spectral weight A(p,\ensuremath{\omega}) of the two-dimensional t-J and Hubbard models has been calculated using exact diagonalization and quantum Monte Carlo techniques, at several densities 0.5\ensuremath{\le}〈n〉\ensuremath{\le}1.0. The photoemission (\ensuremath{\omega}0) region contains two dominant distinct features, namely a low-energy quasiparticle peak with bandwidth of order J, and a broad valence band peak at energies of order t. This behavior persists away from half-filling, as long as the antiferromagnetic correlations are robust. The results give support to theories of the copper oxide materials based on the behavior of holes in antiferromagnets, and they also provide theoretical guidance for the interpretation of experimental photoemission data for the cuprates.

arXiv:cond-mat/9412107•Physical review. B, Condensed matter•May 1, 1995•59 citations
Photoemission spectra for the isotropic two-leg t\ensuremath−Jt\ensuremath{-}Jt\ensuremath−J ladder are calculated at various hole-doping levels using exact diagonalization techniques. Low-energy sharp features caused by short-range antiferromagnetic correlations are observed at finite doping levels close to half-filling, above the naive Fermi momentum. These features should be observable in angle-resolved photoemission experiments. In addition, the formation of a ddd-wave pairing condensate as the ratio Jt\frac{J}{t}tJ​ is increased leads to dynamically generated spectral weight for momenta close to kF{k}_{F}kF​ where the dx2\ensuremath−y2{d}_{{x}^{2}\ensuremath{-}{y}^{2}}dx2\ensuremath−y2​ order parameter is large.
The spectral function $A(\mathbf{q},\ensuremath{\omega})$ of doped $t\ensuremath{-}J$ ladders is presented on clusters with up to $2\ifmmode\times\else\texttimes\fi{}20$ sites at zero temperature applying a recently developed technique that uses up to $\ensuremath{\sim}6\ifmmode\times\else\texttimes\fi{}{10}^{6}$ rung-basis states. Similarities with photoemission results for the two-dimensional cuprates are observed, such as the existence of a gap at $(\ensuremath{\pi},0)$ near half-filling (caused by hole pair formation) and flat bands in its vicinity. These features should be observable in angle-resolved photoemission spectroscopy experiments on ladders. The main result of the paper is the nontrivial evolution of the spectral function from a narrow band at x=0x=0x=0, to a quasinoninteracting band at x> 0.5x>~0.5x> 0.5. It was also observed that the low-energy peaks of a cluster spectra acquire finite linewidths as their energies move away from the chemical potential.
We have numerically investigated the doped t-J ladder using exact diagonalization. We have studied both the limit of strong interchain coupling and isotropic coupling. The ladder scales to the Luther-Emery liquid regime in the strong interchain coupling limit. In this strong coupling limit there is a simple picture of the excitation spectrum that can be continued to explain the behavior at isotropic coupling. At J=0 we have indications of a ferromagnetic ground state. At a large J/t the ladder is phase separated into holes and a Heisenberg ladder. At intermediate coupling the ground state shows hole pairing with a modified d-wave symmetry. The excitation spectrum separates into a limited number of quasiparticles which carry charge +\ensuremath{\Vert}e\ensuremath{\Vert} and spin 1/2 and a triplet magnon mode. At half filling the former vanish but the latter evolves continuously into the magnon band of the spin liquid. At low doping the quasiparticles form a dilute Fermi gas with a strong attraction but simultaneously the Fermi wave vector, as would be measured in photoemission, is large. The dynamical structure factors are calculated and are found to be very similar to calculations on two-dimensional clusters. \textcopyright{} 1996 The American Physical Society.
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 $S(\mathbf{k},\ensuremath{\omega})$ of a generalized $t\ensuremath{-}U\ensuremath{-}J$ Hubbard model away from half filling in a two-leg ladder geometry. The addition of JJJ enhances pairing tendencies. We analyze quantitatively the signatures of pairing in the magnetic excitation spectra. We found that the superconducting pair-correlation strength, that can be estimated independently from ground state properties, is closely correlated with the integrated low-energy magnetic spectral weight in the vicinity of $(\ensuremath{\pi},\ensuremath{\pi})$. In this wave-vector region, robust spin incommensurate features develop with increasing doping. The branch of the spectrum with rung direction wave vector krung=0{k}_{\mathrm{rung}}=0krung​=0 does not change substantially with doping where pairing dominates and thus plays a minor role. We discuss the implications of our results for neutron scattering experiments, where the spin excitation dynamics of hole-doped quasi-one-dimensional magnetic materials can be measured and also address implications for recent resonant inelastic x-ray scattering experiments.
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 $S(\mathbf{k},\ensuremath{\omega})$ of a generalized $t\ensuremath{-}U\ensuremath{-}J$ Hubbard model away from half filling in a two-leg ladder geometry. The addition of JJJ enhances pairing tendencies. We analyze quantitatively the signatures of pairing in the magnetic excitation spectra. We found that the superconducting pair-correlation strength, that can be estimated independently from ground state properties, is closely correlated with the integrated low-energy magnetic spectral weight in the vicinity of $(\ensuremath{\pi},\ensuremath{\pi})$. In this wave-vector region, robust spin incommensurate features develop with increasing doping. The branch of the spectrum with rung direction wave vector krung=0{k}_{\mathrm{rung}}=0krung​=0 does not change substantially with doping where pairing dominates and thus plays a minor role. We discuss the implications of our results for neutron scattering experiments, where the spin excitation dynamics of hole-doped quasi-one-dimensional magnetic materials can be measured and also address implications for recent resonant inelastic x-ray scattering experiments.
Monte Carlo calculations of the irreducible particle-particle interaction on a two-leg Hubbard ladder doped near half-filling are reported. As the temperature is lowered, this interaction develops structure in momentum space similar to the magnetic susceptibility χ(q)χ(q)χ(q) and reflects the development of strong short-range antiferromagnetic correlations. Using this interaction, the eigenfunction of the leading singlet pair eigenvalue is found to have dx2−y2d_{x^2-y^2}dx2−y2​ like symmetry. The single-particle spectral weight is also shown to peak near (π,0)(π,0)(π,0) and (0,π)(0,π)(0,π) when the ratio of the inter- to intra-chain hopping t⊥/t≃1.5t_{\perp}/t\simeq 1.5t⊥​/t≃1.5, leading to an increased tendency for pairing.
The spectral weight A(p,\ensuremath{\omega}) of the two-dimensional t-J and Hubbard models has been calculated using exact diagonalization and quantum Monte Carlo techniques, at several densities 0.5\ensuremath{\le}〈n〉\ensuremath{\le}1.0. The photoemission (\ensuremath{\omega}0) region contains two dominant distinct features, namely a low-energy quasiparticle peak with bandwidth of order J, and a broad valence band peak at energies of order t. This behavior persists away from half-filling, as long as the antiferromagnetic correlations are robust. The results give support to theories of the copper oxide materials based on the behavior of holes in antiferromagnets, and they also provide theoretical guidance for the interpretation of experimental photoemission data for the cuprates.