triqs.gfs.backwd_compat.gf_imtime.GfImTime.density

GfImTime.density(*args, **kwargs)

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 MeshReFreq mesh.

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.