6 citations · 8 across the 2 of their papers we have counts for
2 papers
cond-mat.stat-mech2019★ 2 cited
Diagrammatic Expansion for Positive Spectral Functions in the Steady-State Limit
Markku J. Hyrkäs, Daniel Karlsson, Robert van Leeuwen
Recently, a method was presented for constructing self-energies within many-body perturbation theory that are guaranteed to produce a positive spectral function for equilibrium sys…
math-ph2019★ 6 cited
Contour calculus for many-particle functions
Markku J. Hyrkäs, Daniel Karlsson, Robert van Leeuwen
In non-equilibrium many-body perturbation theory, Langreth rules are an efficient way to extract real-time equations from contour ones. However, the standard rules are not applicab…