Table of Contents
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Properties
Tight Binding objects have the following standard properties:
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Name: a string
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Cell: {a,b,c} defining the unit cell of the system. a, b and c are vectors of length 3 and define the uni-cell vectors.
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Atoms: a list of atoms, their positions within the unit cell and their atomic shells (spin-orbitals). Each element has the format {Atom.Name, Atom.Position, {Atom.Shells}}.
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Hoppings: A list of local and non-local hoppings among spin-orbitals. Each element has the format {spinOrb1, spinOrb1, {a,b,c}, $\{\{t_{\downarrow, \downarrow},t_{\downarrow, \uparrow}\},\{t_{\uparrow, \downarrow}, t_{\uparrow, \uparrow}\}\}$}, where here {a,b,c} is the distance between the two atoms and $\{\{t_{\downarrow, \downarrow},t_{\downarrow, \uparrow}\},\{t_{\uparrow, \downarrow}, t_{\uparrow, \uparrow}\}\}$ defines the hopping matrix elements (in second-quantization language: $ \Sigma t_{\sigma, \sigma'} a^{\dagger}_{\sigma} a_{\sigma'} $)
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Units: {“2Pi”, “Angstrom”, “Absolute”}
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NF: number of fermionic modes
The Units property is a list of three strings with the following contributions:
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Units[1]: Sets the scaling for the reciprocal lattice, e.g., $\vec{r}\cdot\vec{g}=2\pi$ for “2Pi” or $\vec{r}\cdot\vec{g}=1$ for “NoPi”.
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Units[2]: Defines the unit of measurement as “Angstrom”, “Bohr”, or “nanometer”.
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Units[3]: Selects “Absolute” or “Relative” for the definition of atom positions.
Once a Tight Binding object is created, all properties can be assigned except NF, which is determined by the number of orbitals defined in Atoms.
Example
description text
Input
- Example.Quanty
-- some example code
Result
text produced as output
