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Tight binding models for high temperature superconductors
This page lists a set of tightbinding models that are suitable to describe high temperature superconductors
Some of the models have been compiled from the literature for comparison, others are calculated using first principles calculations or adjusted to match experimental measured quantities.
For each model, the hopping parameters are given in a comma separated file (csv), and basic plots of the band structure and Fermi surface are provided for comparison.
The tightbinding file contains lines with the following format:
r_{x}, r_{y}, r_{z}, a, b, Re(t), Im(t)
Here r_{i} is the ith component of the real space vector that describes the hopping process, a and b are integer numbers labeling the orbitals and the last two entries are the real and imaginary part of the hopping (usually given in eV).
The corresponding Bloch Hamiltonian (in orbital representation) can be obtained by a Fourier transform and summation over all lines to yield the matrix H_{ab}.

Models
1 band tight binding model from a DFT calculation using Wien2k. Details on the calculation can be found in the supplement of the associated publication:
A. Kreisel, Peayush Choubey, T. Berlijn, W. Ku, B. M. Andersen, and P. J. Hirschfeld
Phys. Rev. Lett. 114, 217002 (2015) Supplemental Material
To account for correlations, an overall renormalization factor of Z=3 was imposed to the hopping elements. In our work, we used this model to calculate tunneling spectra and conductance maps
close to impurities in Bi2Sr2CaCu2O8, see the following publications for details

A. Kreisel, Peayush Choubey, T. Berlijn, W. Ku, B. M. Andersen, and P. J. Hirschfeld
Phys. Rev. Lett. 114, 217002 (2015)
Interpretation of scanning tunneling quasiparticle interference and impurity states in cuprates
a similar approach and model has been used also in
Peayush Choubey, Andreas Kreisel, T. Berlijn, Brian M. Andersen, P. J. Hirschfeld
Phys. Rev. B 96, 174523 (2017)
Universality of scanning tunneling microscopy in cuprate superconductors
Eigenenergies along high symmetry directions of the Brillouin zone.

Fermi surface of the tight binding model at filling of n=0.425, see source tarball for details on the parameters

Density of states showing the van Hove singularity due to the saddle points of the dispersion at the X and Y points.

Wannier function as generated from an abinitio calculation: Starting point is the crystal structure of BSCCO as described in
Mark S. Hybertsen and L. F. Mattheiss
Phys. Rev. Lett. 60, 1661 (1988)
Electronic band structure of CaBi2Sr2Cu2O8
where one half layer is replaced by vacuum, details in the Supplemental Information of
A. Kreisel, Peayush Choubey, T. Berlijn, W. Ku, B. M. Andersen, and P. J. Hirschfeld
Phys. Rev. Lett. 114, 217002 (2015)
Interpretation of scanning tunneling quasiparticle interference and impurity states in cuprates
The plot shows an isosurface of the Wannier function (red/blue: negative/positive phase), a plane above the surface and the atoms in the elementary cell.
The plot is produced with the program VESTA, the required data files can be downloaded above.

