qtcad.device.strain module

Strain models employed by the single-particle Schrödinger solver for holes.

qtcad.device.strain.bir_pikus(av, b, d)

Compute the deformation potential matrix under the Bir-Pikus formalism for a 4 band \(\mathbf k\cdot \mathbf p\) model. See Sun. Journal of Applied Physics 101, 104503 (2007) for more details.

Parameters

  • av (1d array) – First deformation potential parameter at each global node.

  • b (1d array) – Second deformation potential parameter at each global node.

  • d (1d array) – Third deformation potential parameter at each global node.

Returns

(numpy array) – Deformation potential matrix, Ksi, which describes the coupling to the strain tensor.

Note

The first index is the global node or element index. The next two indices of the Ksi matrix are the x, y, z direction indices. The last two indices are the band indices. The Ksi matrix is given in units of Joules.