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- Bi₂Sr₂CaCu₂O₈+δ (2)
- La₂₋ₓSrₓCuO₄ (2)
- STS (2)
- Scanning tunneling spectroscopy (2)
- ARPES (1)
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- Angle-resolved photoemission (1)
- Ba₁₋ₓKₓBiO₃ (1)
- Bi₂Sr₂CaCu₂O₈₊δ (1)
- Block states (1)
- Compton profiles (1)
- Compton scattering (1)
- Cu (1)
- CuO₂ (1)
- Doping dependence (1)
- Electron excitation spectroscopies (1)
- Electron-hole asymmetry (1)
- FS (1)
- Fermi energy (1)
- Fermi level (1)
- Fermi-liquid physics (1)
- Matrix element effects (1)
- Midgap states (1)
- Momentum density (1)
- Nd2-xCexCuO4 (1)
- Nodeless behavior (1)
- Pr2-xCexCuO4-δ (1)
- Relaxation energies (1)
- Residual three dimensionality (1)
- Spectral decomposition (1)
Articles 1 - 8 of 8
Full-Text Articles in Physics
Bulk Fermi Surface And Momentum Density In Heavily Doped La₂₋ₓsrₓcuo₄ Using High-Resolution Compton Scattering And Positron Annihilation Spectroscopies, W. Al-Sawai, B. Barbiellini, Y. Sakurai, M. Itou, P. Mijnarends, R. Markiewicz, S. Kaprzyk, S. Wakimoto, M. Fujita, S. Basak, H. Lin, Yung Jui Wang, S. Eijt, H. Schut, K. Yamada, A. Bansil
Bulk Fermi Surface And Momentum Density In Heavily Doped La₂₋ₓsrₓcuo₄ Using High-Resolution Compton Scattering And Positron Annihilation Spectroscopies, W. Al-Sawai, B. Barbiellini, Y. Sakurai, M. Itou, P. Mijnarends, R. Markiewicz, S. Kaprzyk, S. Wakimoto, M. Fujita, S. Basak, H. Lin, Yung Jui Wang, S. Eijt, H. Schut, K. Yamada, A. Bansil
Robert Markiewicz
We have observed the bulk Fermi surface (FS) in an overdoped (x=0.3) single crystal of La₂₋ₓSrₓCuO₄ by using Compton scattering. A two-dimensional (2D) momentum density reconstruction from measured Compton profiles yields a clear FS signature in the third Brillouin zone along [100]. The quantitative agreement between density functional theory (DFT) calculations and momentum density experiment suggests that Fermi-liquid physics is restored in the overdoped regime. In particular the predicted FS topology is found to be in good accord with the corresponding experimental data. We find similar quantitative agreement between the measured 2D angular correlation of positron annihilation radiation (2D-ACAR) spectra …
Renormalization Of F Levels Away From The Fermi Energy In Electron Excitation Spectroscopies: Density-Functional Results For Nd2-Xcexcuo4, T. Jarlborg, B. Barbiellini, H. Lin, R. Markiewicz, A. Bansil
Renormalization Of F Levels Away From The Fermi Energy In Electron Excitation Spectroscopies: Density-Functional Results For Nd2-Xcexcuo4, T. Jarlborg, B. Barbiellini, H. Lin, R. Markiewicz, A. Bansil
Robert Markiewicz
Relaxation energies for photoemission where an occupied electronic state is excited and for inverse photoemission where an empty state is filled are calculated within the density-functional theory with application to Nd₂₋ₓCeₓCuO₄. The associated relaxation energies are obtained by computing differences in total energies between the ground state and an excited state in which one hole or one electron is added into the system. The relaxation energies of f electrons are found to be of the order of several eV’s, indicating that f bands will appear substantially away from the Fermi energy (EF) in their spectroscopic images, even if …
Evolution Of Midgap States And Residual Three Dimensionality In La₂₋ₓsrₓcuo₄, S. Sahrakorpi, M. Lindroos, R. Markiewicz, A. Bansil
Evolution Of Midgap States And Residual Three Dimensionality In La₂₋ₓsrₓcuo₄, S. Sahrakorpi, M. Lindroos, R. Markiewicz, A. Bansil
Robert Markiewicz
We carry out extensive first-principles doping-dependent computations of angle-resolved photoemission (ARPES) intensities in La₂₋ₓSrₓCuO₄ over a wide range of binding energies. Intercell hopping and the associated three dimensionality, which is usually neglected in discussing cuprate physics, is shown to play a key role in shaping the ARPES spectra. Despite the obvious importance of strong coupling effects (e.g., the presence of a lower Hubbard band coexisting with midgap states in the doped insulator), a number of salient features of the experimental ARPES spectra are captured to a surprising extent when kz dispersion is properly included in the analysis.
Nodeless D-Wave Superconducting Pairing Due To Residual Antiferromagnetism In Underdoped Pr2-Xcexcuo4-Δ, Tanmoy Das, R. Markiewicz, A. Bansil
Nodeless D-Wave Superconducting Pairing Due To Residual Antiferromagnetism In Underdoped Pr2-Xcexcuo4-Δ, Tanmoy Das, R. Markiewicz, A. Bansil
Robert Markiewicz
We investigate the doping dependence of the penetration depth versus temperature in electron-doped Pr₂₋ₓCeₓCuO4-δ using a model which assumes the uniform coexistence of (mean-field) antiferromagnetism and superconductivity. Despite the presence of a dₓ2₋y2 pairing gap in the underlying spectrum, we find nodeless behavior of the low-T penetration depth in the underdoped case, in accord with experimental results. As doping increases, a linear-in-T behavior of the penetration depth, characteristic of d-wave pairing, emerges as the lower magnetic band crosses the Fermi level and creates a nodal Fermi surface pocket.
Fermi-Surface Study Of Ba₁₋ₓkₓbio₃, S. Sahrakorpi, B. Barbiellini, R. Markiewicz, S. Kaprzyk, M. Lindroos, A. Bansil
Fermi-Surface Study Of Ba₁₋ₓkₓbio₃, S. Sahrakorpi, B. Barbiellini, R. Markiewicz, S. Kaprzyk, M. Lindroos, A. Bansil
Robert Markiewicz
We present all-electron computations of the three-dimensional (3D) Fermi surfaces (FS’s) in Ba₁₋ₓKₓBiO₃ for a number of different compositions based on the self-consistent Korringa-Kohn-Rostoker coherent-potential-approximation approach for incorporating the effects of Ba/K substitution. By assuming a simple cubic structure throughout the composition range, the evolution of the nesting and other features of the FS of the underlying pristine phase is correlated with the onset of various structural transitions with K doping. A parametrized scheme for obtaining an accurate 3D map of the FS in Ba₁₋ₓKₓBiO₃ for an arbitrary doping level is developed. We remark on the puzzling differences between the …
Spectral Decomposition And Matrix Element Effects In Scanning Tunneling Spectroscopy Of Bi₂Sr₂Cacu₂O₈₊Δ, Jouko Nieminen, Ilpo Suominen, R. Markiewicz, Hsin Lin, A. Bansil
Spectral Decomposition And Matrix Element Effects In Scanning Tunneling Spectroscopy Of Bi₂Sr₂Cacu₂O₈₊Δ, Jouko Nieminen, Ilpo Suominen, R. Markiewicz, Hsin Lin, A. Bansil
Robert Markiewicz
We present a Green’s function-based framework for modeling the scanning tunneling spectrum from the normal as well as the superconducting state of complex materials where the nature of the tunneling process—i.e., the effect of the tunneling “matrix element,” is properly taken into account. The formalism is applied to the case of optimally doped Bi₂Sr₂CaCu2=₂O8+δ (Bi2212) high-Tc superconductor using a large tight-binding basis set of electron and hole orbitals. The results show clearly that the spectrum is modified strongly by the effects of the tunneling matrix element and that it is not a simple replica of the local density of …
Induced Superconductivity In Noncuprate Layers Of The Bi₂Sr₂Cacu₂O₈+Δ High-Temperature Superconductor: Modeling Of Scanning Tunneling Spectra, Ilpo Suominen, Jouko Nieminen, R. Markiewicz, A. Bansil
Induced Superconductivity In Noncuprate Layers Of The Bi₂Sr₂Cacu₂O₈+Δ High-Temperature Superconductor: Modeling Of Scanning Tunneling Spectra, Ilpo Suominen, Jouko Nieminen, R. Markiewicz, A. Bansil
Robert Markiewicz
We analyze how the coherence peaks observed in scanning tunneling spectroscopy (STS) of cuprate high-temperature superconductors are transferred from the cuprate layer to the oxide layers adjacent to the STS microscope tip. For this purpose, we have carried out a realistic multiband calculation for the superconducting state of Bi₂Sr₂CaCu₂O₈₊δ (Bi2212) assuming a short-range d-wave pairing interaction confined to the nearest-neighbor Cu dₓ2₋y2 orbitals. The resulting anomalous matrix elements of the Green’s function allow us to monitor how pairing is then induced not only within the cuprate bilayer but also within and across other layers and …
Origin Of The Electron-Hole Asymmetry In The Scanning Tunneling Spectrum Of The High-Temperature Bi₂Sr₂Cacu₂O₈+Δ Superconductor, Jouko Nieminen, Hsin Lin, R. Markiewicz, A. Bansil
Origin Of The Electron-Hole Asymmetry In The Scanning Tunneling Spectrum Of The High-Temperature Bi₂Sr₂Cacu₂O₈+Δ Superconductor, Jouko Nieminen, Hsin Lin, R. Markiewicz, A. Bansil
Robert Markiewicz
We have developed a material specific theoretical framework for modeling scanning tunneling spectroscopy (STS) of high-temperature superconducting materials in the normal as well as the superconducting state. Results for Bi₂Sr₂CaCu₂O₈₊δ (Bi2212) show clearly that the tunneling process strongly modifies the STS spectrum from the local density of states of the dₓ2₋y2 orbital of Cu. The dominant tunneling channel to the surface Bi involves the dₓ2₋y2 orbitals of the four neighboring Cu atoms. In accord with experimental observations, the computed spectrum displays a remarkable asymmetry between the processes of electron injection and extraction, which arises from contributions of Cu dz2 and …