magnopy.LSWT.G_inv

method

LSWT.G_inv(k, relative=False)

Inverse of the transformation matrix to the new bosonic operators.

\[b_{\alpha}(\boldsymbol{k}) = \sum_{\beta} (\mathcal{G}^{-1})_{\alpha, \beta}(\boldsymbol{k}) \mathcal{A}_{\beta}(\boldsymbol{k})\]

Parameters:

k(3,) array-like

Reciprocal vector

relativebool, default False

If relative=True, then k is interpreted as given relative to the reciprocal unit cell. Otherwise it is interpreted as given in absolute coordinates.

Returns:

G_inv(M, 2M) numpy.ndarray

Transformation matrix from the original boson operators. Note that this function returns \((\mathcal{G})^{-1}\) for convenience.

See also

LSWT.diagonalize

LSWT.omega

LSWT.delta

Examples

>>> import magnopy
>>> spinham = magnopy.examples.cubic_ferro_nn()
>>> lswt = magnopy.LSWT(spinham=spinham, spin_directions=[[0, 0, 1]])
>>> lswt.G_inv(k=[0,0,0.5], relative=True)
array([[1.+0.j, 0.+0.j]])