triqs.gfs.gf.Gf.density
- Gf.density(*args, **kwargs)[source]
Compute the single-particle density matrix.
Equivalent to \(\langle c^\dagger_i c_j \rangle\) evaluated from the diagonal-frequency / equal-time limit of the Green’s function.
- Parameters:
- betafloat, optional
Inverse temperature. Required only for finite-temperature density evaluation on a
MeshReFreqmesh.
- Returns:
- density_matrixnumpy.ndarray
Single-particle density matrix of shape
target_shape.
Notes
Only available for single-mesh Green’s functions on a Matsubara, real-frequency or Legendre mesh.