SIAM (QSZ)
This is the single-impurity single-orbital Anderson model with conserved total charge (Q) and z-component of total spin (Sz) quantum numbers.
Hamiltonian
\[H_\mathrm{imp} = \epsilon_1 n + U_1 n_\uparrow n_\downarrow + B_1 S_z\]
with
\[S_z = \frac{1}{2} \left( n_\uparrow - n_\downarrow \right)\]
Parameters
\(\epsilon_1\),
eps1, energy level\(U_1\),
U1, electron-electron interaction\(B_1\),
B1, magnetic field (Zeeman splitting)
Expectation values
\(\langle n \rangle\),
n_d, impurity occupancy\(\langle n^2 \rangle\),
n_d^2, impurity occupancy squared\(\langle \sum_\sigma d^\dagger_\sigma f_{0\sigma} + \text{h.c.} \rangle\),
hop0, hopping between the impurity and the zero-th site of the Wilson chain\(\langle S_z \rangle\),
SZd, spin polarization (magnetization)
Structure of Green’s functions
Two blocks, up and dn, scalar-valued (1x1 matrix)
Dynamic susceptibilities
Dynamic spin and charge susceptibilities are calculated.