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- Topological insulators (2)
- Angle-resolved photoemission (ARPES) (1)
- Bi₂Sr₂CaCu₂O₈ (1)
- Bi₂Te₃ (1)
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- Coexisting pseudogap (1)
- Cuprates (1)
- Dirac cone surface states (1)
- Doping (1)
- Fermi surfaces (FSs) (1)
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- Large spectral weight broadening (1)
- Matrix element effects (1)
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- Mott-gap energy scales (1)
- Photoemission spectra of cuprates (1)
- Spectral weight transfer (1)
- Spectroscopies (1)
- Spectrum analysis (1)
- Spin texture (1)
- Waterfall effect (1)
Articles 1 - 4 of 4
Full-Text Articles in Physics
Coexisting Pseudogap, Charge-Transfer-Gap, And Mott-Gap Energy Scales In The Resonant Inelastic X-Ray Scattering Spectra Of Electron-Doped Cuprate Superconductors, Susmita Basak, Tanmoy Das, Hsin Lin, M. Z. Hasan, R. S. Markiewicz, A. Bansil
Coexisting Pseudogap, Charge-Transfer-Gap, And Mott-Gap Energy Scales In The Resonant Inelastic X-Ray Scattering Spectra Of Electron-Doped Cuprate Superconductors, Susmita Basak, Tanmoy Das, Hsin Lin, M. Z. Hasan, R. S. Markiewicz, A. Bansil
Susmita Basak
We present a computation of Cu K-edge resonant inelastic x-ray scattering (RIXS) spectra for electron-doped cuprates, which includes coupling to bosonic fluctuations. Comparison with experiment over a wide range of energy and momentum transfers allows us to identify the signatures of three key normal-state energy scales: the pseudogap, charge-transfer gap, and Mott gap. The calculations involve a three-band Hubbard Hamiltonian based on dₓ2₋y2 and O pₓ, py orbitals, with a self-energy correction which arises due to spin and charge fluctuations. Our theory reproduces characteristic features, e.g., gap collapse, large spectral weight broadening, and spectral weight transfer as a function of …
Origin Of The High-Energy Kink In The Photoemission Spectrum Of The High-Temperature Superconductor Bi₂Sr₂Cacu₂O₈, Susmita Basak, Tanmoy Das, Hsin Lin, J. Nieminen, M. Lindroos, R. S. Markiewicz, A. Bansil
Origin Of The High-Energy Kink In The Photoemission Spectrum Of The High-Temperature Superconductor Bi₂Sr₂Cacu₂O₈, Susmita Basak, Tanmoy Das, Hsin Lin, J. Nieminen, M. Lindroos, R. S. Markiewicz, A. Bansil
Susmita Basak
The high-energy kink or the waterfall effect seen in the photoemission spectra of cuprates is suggestive of the coupling of quasiparticles to a high-energy bosonic mode with implications for the mechanism of superconductivity. Recent experiments, however, indicate that this effect may be an artifact produced entirely by matrix element effects, i.e., by the way the photoemitted electron couples to incident photons in the emission process. In order to address this issue directly, we have carried out realistic computations of the photointensity in Bi₂Sr₂CaCu₂O₈ where the effects of the matrix element are included together with those of the corrections to the …
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 …
Spin Texture On The Warped Dirac-Cone Surface States In Topological Insulators, Susmita Basak, Hsin Lin, L. A. Wray, S. Y. Xu, L. Fu, M. Z. Hasan, A. Bansil
Spin Texture On The Warped Dirac-Cone Surface States In Topological Insulators, Susmita Basak, Hsin Lin, L. A. Wray, S. Y. Xu, L. Fu, M. Z. Hasan, A. Bansil
Susmita Basak
We have investigated the nature of surface states in the Bi₂Te₃ family of three-dimensional topological insulators using first-principles calculations as well as a model Hamiltonian approach. When the surface Dirac cone is warped due to Dresselhaus spin-orbit coupling in rhombohedral structures, the spin acquires a finite out-of-the-plane component. We provide a simple, minimal model to describe the in-plane spin texture of the warped surface Dirac cone observed in experiments where spins are seen to be not aligned perpendicular to the electron momentum. Our k·p model calculation reveals that this in-plane spin texture requires fifth-order Dresselhaus spin-orbit coupling terms