Discretized Thermal Green's Functions

Abstract

We present a spectral weight conserving formalism for Fermionic thermal Green's functions that are discretized in imaginary time and thus periodic in imaginary ("Matsubara") frequency. The formalism requires a generalization of the Dyson equation and the Baym-Kadanoff-Luttinger-Ward functional for the free energy. A conformal transformation is used to analytically continue the periodized Matsubara Green's function to the continuous real axis in a way that conserves the discontinuity at t=0 of the corresponding real-time Green's function. For given discretization the method allows numerical Green's function calculations of very high precision and it appears to give a well controlled convergent approximation as we decrease the discretization interval. The ideas are tested on Dynamical Mean Field Theory calculations of the paramagnetic Hubbard model.

References in corpus (3)

• A finite-frequency functional RG approach to the single impurity Anderson model
• Finite-temperature linear conductance from the Matsubara Green function without analytic continuation to the real axis
• The Dynamical Mean Field Theory phase space extension and critical properties of the finite temperature Mott transition

Cited by in corpus (2)

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