gftool.siam.gf0_loc_gr_t

gftool.siam.gf0_loc_gr_t(tt, e_onsite, e_bath, hopping, beta)[source]

Noninteracting greater local Green’s function for the impurity.

Parameters:
tt(…) float np.ndarray

Time variable. Note that the retarded Green’s function is 0 for tt<0.

e_onsite(…) float np.ndarray

On-site energy of the impurity site.

e_bath(…, Nb) float np.ndarray

On-site energy of the bath sites.

hopping(…, Nb) complex np.ndarray

Hopping matrix element between impurity and the bath sites.

betafloat

The inverse temperature \(beta = 1/k_B T\).

Returns:
(…) complex np.ndarray

Greater Green’s function of the impurity site.