  We describe a method to obtain the reduced density matrix (RDM) correct up to
second order in system-bath coupling in \emph{nonequilibrium} steady state
situations. The RDM is obtained via a scheme based on analytic continuation,
using the time-local Redfield-like quantum master equation, which was earlier
used by the same authors [J. Chem. Phys. \textbf{136}, 194110 (2012)] to obtain
the correct thermal equilibrium description. This nonequilibrium modified
Redfield solution is then corroborated with the exact RDM obtained via the
nonequilibrium Green's function technique for the quantum harmonic oscillator.
Lastly, the scheme is compared to different quantum master equations (QMEs),
namely the time-local Redfield-like and the Lindblad-like QMEs, in order to
illustrate the differences between each of these approaches.

Statistical Mechanics