gftool.bethe_hilbert_transform

gftool.bethe_hilbert_transform(xi, half_bandwidth)

Hilbert transform of non-interacting DOS of the Bethe lattice.

The Hilbert transform is defined as:

\[\tilde{D}(ξ) = ∫_{-∞}^{∞}dϵ \frac{DOS(ϵ)}{ξ − ϵ}\]

The lattice Hilbert transform is the same as the non-interacting Green’s function.

Parameters:
xicomplex array_like or complex

Point at which the Hilbert transform is evaluated.

half_bandwidthfloat

Half-bandwidth of the DOS of the Bethe lattice.

Returns:
complex np.ndarray or complex

Hilbert transform of xi.

Notes

Relation between nearest neighbor hopping t and half-bandwidth D:

\[2t = D\]