bilayer
- sisl.geom.bilayer(bond: float = 1.42, bottom_atoms: sisl.typing.AtomsLike | None = None, top_atoms: sisl.typing.AtomsLike | None = None, stacking: str = 'AB', twist=(0, 0), separation: float = 3.35, ret_angle: bool = False, layer: str = 'both') Geometry
Commensurate unit cell of a hexagonal bilayer structure, possibly with a twist angle.
This routine follows the prescription of twisted bilayer graphene found in [10].
Notes
This routine may change in the future to force some of the arguments.
- Parameters:
bond (float) – bond length between atoms in the honeycomb lattice
bottom_atoms (sisl.typing.AtomsLike | None) – atom (or atoms) in the bottom layer. Defaults to
Atom(6)top_atoms (sisl.typing.AtomsLike | None) – atom (or atoms) in the top layer, defaults to bottom_atom
stacking ({'AB', 'AA', 'BA'}) – stacking sequence of the bilayer, where XY means that site X in bottom layer coincides with site Y in top layer
twist (tuple of int, optional) – integer coordinates (m, n) defining a commensurate twist angle
separation (float) – distance between the two layers
ret_angle (bool) – return the twist angle (in degrees) in addition to the geometry instance
layer ({'both', 'bottom', 'top'}) – control which layer(s) to return
- Return type: