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Related papers: Tight-binding models for the new iron based superc…

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We generalize solid-state tight-binding techniques for the spectral analysis of large superconducting circuits. We find that tight-binding states can be better suited for approximating the low-energy excitations than charge-basis states, as…

Quantum Physics · Physics 2021-09-22 D. K. Weiss , Wade DeGottardi , Jens Koch , D. G. Ferguson

Based on a two-orbital model and taking into account the presence of the impurity, we studied theoretically the electronic structure in the vortex core of the iron-Pnictide superconducting materials. The vortex is pinned when the impurity…

Superconductivity · Physics 2011-12-01 Tao Zhou , Z. D. Wang , Yi Gao , C. S. Ting

First principles calculations are used to establish that the electronic structure of graphene ribbons with zig-zag edges is unstable with respect to magnetic polarisation of the edge states. The magnetic interaction between edge states is…

Materials Science · Physics 2015-06-25 L. Pisani , J. A. Chan , B. Montanari , N. M. Harrison

The level of electronic correlation has been one of the key questions in understanding the nature of superconductivity. Among the iron-based superconductors, the iron chalcogenide family exhibits the strongest electron correlations. To…

The electronic structure, when restricted to the d-band approximation, is a computational model that is both efficient and useful for describing transition metals. In the absence of considering delocalized sp-states, this approximation…

Materials Science · Physics 2025-08-05 Jacques R. Eone

Motivated by the newly-discovered intercalated iron chalcogenide superconductors, we construct a single orbital tight-binding model for topological insulators on the square lattice with a perfect vacancy superstructure. We find that such…

Strongly Correlated Electrons · Physics 2015-03-19 Xiao-Yong Feng , Hua Chen , Chao Cao , Jianhui Dai

An empirical $s_cp^3_a$ tight-binding (TB) model is applied to the investigation of electronic states in semiconductor quantum dots. A basis set of three $p$-orbitals at the anions and one $s$-orbital at the cations is chosen. Matrix…

Other Condensed Matter · Physics 2009-11-11 Stefan Schulz , Gerd Czycholl

First-principles calculations were performed to investigate the electronic structure of two-dimensional (2-D) Ge, Sn, and Pb without and with the presence of an external electric field in combination with spin-orbit coupling. Tight-binding…

Electron correlations play a central role in iron-based superconductors. In these systems, multiple Fe $3d$-orbitals are active in the low-energy physics, and they are not all degenerate. For these reasons, the role of orbital-selective…

Superconductivity · Physics 2021-05-06 Rong Yu , Haoyu Hu , Emilian M. Nica , Jian-Xin Zhu , Qimiao Si

The unconventional superconductivity in the newly discovered iron-based superconductors is intimately related to its multi-band/multi-orbital nature. Here we report the comprehensive orbital characters of the low-energy three-dimensional…

The emergence of nematic electronic states accompanied by a structural phase transition is a recurring theme in many correlated electron materials, including the high-temperature copper oxide- and iron-based superconductors. We provide…

The tight binding model is a minimal electronic structure model for molecular modelling and simulation. We show that the total energy in this model can be decomposed into site energies, that is, into contributions from each atomic site…

Numerical Analysis · Mathematics 2015-06-19 Huajie Chen , Christoph Ortner

We propose a superlattice model to describe superconductivity in layered materials, such as the borocarbide families with the chemical formul\ae\ $RT_2$B$_2$C and $RT$BC, with $R$ being (essentially) a rare earth, and $T$ a transition…

Superconductivity · Physics 2009-11-10 Thereza Paiva , Mohammed El-Massalami , Raimundo R. dos Santos

We provide a comprehensive analysis of the prominent tight-binding (TB) models for transition metal dichalcogenides (TMDs) available in the literature. We inspect the construction of these TB models, discuss their parameterization used and…

Materials Science · Physics 2024-06-25 Bert Jorissen , Lucian Covaci , Bart Partoens

Electronic states in quasiperiodic crystals generally preclude a Bloch description, rendering them simultaneously fascinating and enigmatic. Owing to their complexity and relative scarcity, quasiperiodic crystals are underexplored relative…

Electron-electron interactions are at the origin of many exotic electronic properties of materials which have emerged from recent experimental observations. The main important phenomena discovered are related with electronic magnetic…

Strongly Correlated Electrons · Physics 2015-05-19 Henri Alloul

We examine the relevance of magneto-elastic coupling to describe the complex magnetic and structural behaviour of the different classes of the iron superconductors. We model the system as a two-dimensional metal whose magnetic excitations…

Strongly Correlated Electrons · Physics 2015-05-27 I. Paul

The electronic structure is found to be understandable in terms of free-atom term values and universal interorbital coupling parameters, since self-consistent tight-binding calculations indicate that Coulomb shifts of the d-state energies…

Materials Science · Physics 2009-11-13 Walter A. Harrison

We present a high-accuracy procedure for electronic structure calculations of strongly correlated materials. To address limitations in current electronic structure methods, we employ density functional theory in combination with the…

Tight-binding models provide great insight and are a low-cost alternative to \emph{ab initio} methods for calculation of a material's electronic structure. These models are used to calculate optical responses, including nonlinear optical…

Materials Science · Physics 2025-09-29 Andreas Ghosh , Aaron M. Schankler , Andrew M. Rappe