Recently Han and Heary proposed an approach to steady-state quantum transport
through mesoscopic structures, which maps the non-equilibrium problem onto a
family of auxiliary quantum impurity systems subject to imaginary voltages. We
employ continuous-time quantum Monte-Carlo solvers to calculate accurate
imaginary time data for the auxiliary models. The spectral function is obtained
from a maximum entropy analytical continuation in both Matsubara frequency and
complexified voltage. To enable the analytical continuation we construct a
kernel which is compatible with the analytical structure of the theory. While
it remains a formidable task to extract reliable spectral functions from this
unbiased procedure, particularly for large voltages, our results indicate that
the method in principle yields results in agreement with those obtained by
other methods
