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Influence Of The Third Dimension Of Quasi-Two-Dimensional Cuprate Superconductors On Angle-Resolved Photoemission Spectra, A. Bansil, M. Lindroos, S. Sahrakorpi, R. S. Markiewicz
Influence Of The Third Dimension Of Quasi-Two-Dimensional Cuprate Superconductors On Angle-Resolved Photoemission Spectra, A. Bansil, M. Lindroos, S. Sahrakorpi, R. S. Markiewicz
Robert Markiewicz
Angle-resolved photoemission spectroscopy (ARPES) presents significant simplifications in analyzing strictly two-dimensional (2D) materials, but even the most anisotropic physical systems display some residual three-dimensionality. Here we demonstrate how this third dimension manifests itself in ARPES spectra of quasi-2D materials by considering the example of the cuprate Bi₂Sr₂CaCu₂O₈ (Bi2212). The intercell, interlayer hopping, which is responsible for kz dispersion of the bands, is found to induce an irreducible broadening to the ARPES line shapes with a characteristic dependence on the in-plane momentum k‖. Our study suggests that ARPES line shapes can provide a direct spectroscopic window for establishing the existence of …
Magnetic Mechanism Of Quasiparticle Pairing In Hole-Doped Cuprate Superconductors, R. S. Markiewicz, A. Bansil
Magnetic Mechanism Of Quasiparticle Pairing In Hole-Doped Cuprate Superconductors, R. S. Markiewicz, A. Bansil
Robert Markiewicz
We have computed α2F’s for the hole-doped cuprates within the framework of the one-band Hubbard model, where the full magnetic response of the system is treated properly. The d-wave pairing weight α2Fd is found not only to contain a low-energy peak due to excitations near (π,π) expected from neutron-scattering data but also to display substantial spectral weight at higher energies due to contributions from other parts of the Brillouin zone as well as pair-breaking ferromagnetic excitations at low energies. The resulting solutions of the Eliashberg equations yield transition temperatures and gaps comparable to the experimentally observed values, suggesting that magnetic …
Gutzwiller Magnetic Phase Diagram Of The Cuprates, R. S. Markiewicz, J. Lorenzana, G. Seibold, A. Bansil
Gutzwiller Magnetic Phase Diagram Of The Cuprates, R. S. Markiewicz, J. Lorenzana, G. Seibold, A. Bansil
Robert Markiewicz
A general constructive procedure is presented for analyzing magnetic instabilities in two-dimensional materials, in terms of (predominantly) double nesting, and applied to Hartree-Fock plus random-phase approximation (HF+RPA) and Gutzwiller approximation plus RPA calculations of the Hubbard model. Applied to the cuprates, it is found that competing magnetic interactions are present only for hole doping, between half filling and the Van Hove singularity. While HF+RPA instabilities are present at all dopings (for sufficiently large Hubbard U), in a Gutzwiller approximation they are restricted to a doping range close to the range of relevance for the physical cuprates. The same model would …
One-Band Tight-Binding Model Parametrization Of The High-Tc Cuprates Including The Effect Of Kz Dispersion, R. S. Markiewicz, S. Sahrakorpi, M. Lindroos, Hsin Lin, A. Bansil
One-Band Tight-Binding Model Parametrization Of The High-Tc Cuprates Including The Effect Of Kz Dispersion, R. S. Markiewicz, S. Sahrakorpi, M. Lindroos, Hsin Lin, A. Bansil
Robert Markiewicz
We discuss the effects of interlayer hopping and the resulting kz dispersion in the cuprates within the framework of the one-band tight-binding model Hamiltonian. Specific forms of the dispersion relations in terms of the in-plane hopping parameters t, t′, t″, and t‴ and the effective interlayer hopping tz in La₂₋ₓSrₓCuO₄ (LSCO) and Nd₂₋ₓCeₓCuO₄ (NCCO) and the added intracell hopping tbi between the CuO₂ bilayers in Bi₂Sr₂CaCu₂O₈ (Bi2212) are presented. The values of the “bare” parameters are obtained via fits with the first-principles local-density-approximation- (LDA-) based band structures in LSCO, NCCO, and Bi2212. The corresponding “dressed” parameter sets which account for …
Paramagnon-Induced Dispersion Anomalies In The Cuprates, R. S. Markiewicz, S. Sahrakorpi, A. Bansil
Paramagnon-Induced Dispersion Anomalies In The Cuprates, R. S. Markiewicz, S. Sahrakorpi, A. Bansil
Robert Markiewicz
We report the self-energy associated with random-phase approximation magnetic susceptibility in the hole-doped Bi₂Sr₂CuO₆ (Bi2201) and the electron-doped Nd₂₋ₓCeₓCuO₄ (NCCO) in the overdoped regime within the framework of a one-band Hubbard model. A strong weight is found in the magnetic spectrum around (π,0) at about 360 meV in Bi2201 and 640 meV in NCCO, which yields dispersion anomalies in accord with the recently observed “waterfall” effects in the cuprates.
Optical Model-Solution To The Competition Between A Pseudogap Phase And A Charge-Transfer-Gap Phase In High-Temperature Cuprate Superconductors, Tanmoy Das, R. S. Markiewicz, A. Bansil
Optical Model-Solution To The Competition Between A Pseudogap Phase And A Charge-Transfer-Gap Phase In High-Temperature Cuprate Superconductors, Tanmoy Das, R. S. Markiewicz, A. Bansil
Robert Markiewicz
We present a theoretical framework for a quantitative understanding of the full doping dependence of the optical spectra of the cuprates. In accord with experimental observations, the computed spectra show how the high-energy charge-transfer (CT) gap features persist in the overdoped regime even after the midinfrared (MIR) peak originating from the pseudogap has collapsed in a quantum critical point. In this way, we reconcile the opposing tendencies of the MIR and CT peaks to shift in opposite directions in the optical spectra with increasing doping. The competition between the pseudogap and the CT gap also results in rapid loss of …
One-Band Tight-Binding Model Parametrization Of The High-Tc Cuprates Including The Effect Of Kz Dispersion, R. S. Markiewicz, S. Sahrakorpi, M. Lindroos, Hsin Lin, A. Bansil
One-Band Tight-Binding Model Parametrization Of The High-Tc Cuprates Including The Effect Of Kz Dispersion, R. S. Markiewicz, S. Sahrakorpi, M. Lindroos, Hsin Lin, A. Bansil
Hsin Lin
We discuss the effects of interlayer hopping and the resulting kz dispersion in the cuprates within the framework of the one-band tight-binding model Hamiltonian. Specific forms of the dispersion relations in terms of the in-plane hopping parameters t, t′, t″, and t‴ and the effective interlayer hopping tz in La₂₋ₓSrₓCuO₄ (LSCO) and Nd₂₋ₓCeₓCuO₄ (NCCO) and the added intracell hopping tbi between the CuO₂ bilayers in Bi₂Sr₂CaCu₂O₈ (Bi2212) are presented. The values of the “bare” parameters are obtained via fits with the first-principles local-density-approximation- (LDA-) based band structures in LSCO, NCCO, and Bi2212. The corresponding “dressed” parameter sets which account for …
Theoretical Modeling Of Various Spectroscopies For Cuprates And Topological Insulators, Susmita Basak
Theoretical Modeling Of Various Spectroscopies For Cuprates And Topological Insulators, Susmita Basak
Susmita Basak
Spectroscopies resolved highly in momentum, energy and/or spatial dimensions are playing an important role in unraveling key properties of wide classes of novel materials. However, spectroscopies do not usually provide a direct map of the underlying electronic spectrum, but act as a complex `filter' to produce a `mapping' of the underlying energy levels, Fermi surfaces (FSs) and excitation spectra. The connection between the electronic spectrum and the measured spectra is described as a generalized `matrix element effect'. The nature of the matrix element involved differs greatly between different spectroscopies. For example, in angle-resolved photoemission (ARPES) an incoming photon knocks out …
Gutzwiller Magnetic Phase Diagram Of The Cuprates, R. S. Markiewicz, J. Lorenzana, G. Seibold, A. Bansil
Gutzwiller Magnetic Phase Diagram Of The Cuprates, R. S. Markiewicz, J. Lorenzana, G. Seibold, A. Bansil
Arun Bansil
A general constructive procedure is presented for analyzing magnetic instabilities in two-dimensional materials, in terms of (predominantly) double nesting, and applied to Hartree-Fock plus random-phase approximation (HF+RPA) and Gutzwiller approximation plus RPA calculations of the Hubbard model. Applied to the cuprates, it is found that competing magnetic interactions are present only for hole doping, between half filling and the Van Hove singularity. While HF+RPA instabilities are present at all dopings (for sufficiently large Hubbard U), in a Gutzwiller approximation they are restricted to a doping range close to the range of relevance for the physical cuprates. The same model would …
Paramagnon-Induced Dispersion Anomalies In The Cuprates, R. S. Markiewicz, S. Sahrakorpi, A. Bansil
Paramagnon-Induced Dispersion Anomalies In The Cuprates, R. S. Markiewicz, S. Sahrakorpi, A. Bansil
Arun Bansil
We report the self-energy associated with random-phase approximation magnetic susceptibility in the hole-doped Bi₂Sr₂CuO₆ (Bi2201) and the electron-doped Nd₂₋ₓCeₓCuO₄ (NCCO) in the overdoped regime within the framework of a one-band Hubbard model. A strong weight is found in the magnetic spectrum around (π,0) at about 360 meV in Bi2201 and 640 meV in NCCO, which yields dispersion anomalies in accord with the recently observed “waterfall” effects in the cuprates.
Failure Of T-J Models In Describing Doping Evolution Of Spectral Weight In X-Ray Scattering, Optical, And Photoemission Spectra Of Cuprates, R. S. Markiewicz, Tanmoy Das, A. Bansil
Failure Of T-J Models In Describing Doping Evolution Of Spectral Weight In X-Ray Scattering, Optical, And Photoemission Spectra Of Cuprates, R. S. Markiewicz, Tanmoy Das, A. Bansil
Arun Bansil
We have analyzed experimental evidence for an anomalous transfer of spectral weight from high-to low-energy scales in both electron-and hole-doped cuprates as a function of doping. X-ray scattering, optical, and photoemission spectra are all found to show that the high-energy spectral weight decreases with increasing doping at a rate much faster than predictions of the large U-limit calculations. The observed doping evolution is however well described by an intermediate coupling scenario where the effective Hubbard U is comparable to the bandwidth. The experimental spectra across various spectroscopies are inconsistent with fixed-U exact diagonalization or quantum Monte Carlo calculations, and suggest …
Influence Of The Third Dimension Of Quasi-Two-Dimensional Cuprate Superconductors On Angle-Resolved Photoemission Spectra, A. Bansil, M. Lindroos, S. Sahrakorpi, R. S. Markiewicz
Influence Of The Third Dimension Of Quasi-Two-Dimensional Cuprate Superconductors On Angle-Resolved Photoemission Spectra, A. Bansil, M. Lindroos, S. Sahrakorpi, R. S. Markiewicz
Arun Bansil
Angle-resolved photoemission spectroscopy (ARPES) presents significant simplifications in analyzing strictly two-dimensional (2D) materials, but even the most anisotropic physical systems display some residual three-dimensionality. Here we demonstrate how this third dimension manifests itself in ARPES spectra of quasi-2D materials by considering the example of the cuprate Bi₂Sr₂CaCu₂O₈ (Bi2212). The intercell, interlayer hopping, which is responsible for kz dispersion of the bands, is found to induce an irreducible broadening to the ARPES line shapes with a characteristic dependence on the in-plane momentum k‖. Our study suggests that ARPES line shapes can provide a direct spectroscopic window for establishing the existence of …
Magnetic Mechanism Of Quasiparticle Pairing In Hole-Doped Cuprate Superconductors, R. S. Markiewicz, A. Bansil
Magnetic Mechanism Of Quasiparticle Pairing In Hole-Doped Cuprate Superconductors, R. S. Markiewicz, A. Bansil
Arun Bansil
We have computed α2F’s for the hole-doped cuprates within the framework of the one-band Hubbard model, where the full magnetic response of the system is treated properly. The d-wave pairing weight α2Fd is found not only to contain a low-energy peak due to excitations near (π,π) expected from neutron-scattering data but also to display substantial spectral weight at higher energies due to contributions from other parts of the Brillouin zone as well as pair-breaking ferromagnetic excitations at low energies. The resulting solutions of the Eliashberg equations yield transition temperatures and gaps comparable to the experimentally observed values, suggesting that magnetic …
Optical Model-Solution To The Competition Between A Pseudogap Phase And A Charge-Transfer-Gap Phase In High-Temperature Cuprate Superconductors, Tanmoy Das, R. S. Markiewicz, A. Bansil
Optical Model-Solution To The Competition Between A Pseudogap Phase And A Charge-Transfer-Gap Phase In High-Temperature Cuprate Superconductors, Tanmoy Das, R. S. Markiewicz, A. Bansil
Arun Bansil
We present a theoretical framework for a quantitative understanding of the full doping dependence of the optical spectra of the cuprates. In accord with experimental observations, the computed spectra show how the high-energy charge-transfer (CT) gap features persist in the overdoped regime even after the midinfrared (MIR) peak originating from the pseudogap has collapsed in a quantum critical point. In this way, we reconcile the opposing tendencies of the MIR and CT peaks to shift in opposite directions in the optical spectra with increasing doping. The competition between the pseudogap and the CT gap also results in rapid loss of …
One-Band Tight-Binding Model Parametrization Of The High-Tc Cuprates Including The Effect Of Kz Dispersion, R. Markiewicz, S. Sahrakorpi, M. Lindroos, Hsin Lin, A. Bansil
One-Band Tight-Binding Model Parametrization Of The High-Tc Cuprates Including The Effect Of Kz Dispersion, R. Markiewicz, S. Sahrakorpi, M. Lindroos, Hsin Lin, A. Bansil
Arun Bansil
We discuss the effects of interlayer hopping and the resulting kz dispersion in the cuprates within the framework of the one-band tight-binding model Hamiltonian. Specific forms of the dispersion relations in terms of the in-plane hopping parameters t, t′, t″, and t‴ and the effective interlayer hopping tz in La₂₋ₓSrₓCuO₄ (LSCO) and Nd₂₋ₓCeₓCuO₄ (NCCO) and the added intracell hopping tbi between the CuO₂ bilayers in Bi₂Sr₂CaCu₂O₈ (Bi2212) are presented. The values of the “bare” parameters are obtained via fits with the first-principles local-density-approximation- (LDA-) based band structures in LSCO, NCCO, and Bi2212. The corresponding “dressed” parameter sets which account for …