  Non-equilibrium Green's function (NEGF) and quantum master equation (QME) are
two main classes of approaches for electronic transport. We discuss various
Floquet variances of these formalisms for transport properties of a quantum dot
driven via interaction with an external periodic field. We first derived two
versions of the Floquet NEGF. We also explore an ansatz of the Floquet NEGF
formalism for the interacting systems. In addition, we derived two versions of
Floquet QME in the weak interaction regime. With each method, we elaborate on
the evaluation of the expectation values of the number and current operators.
We examined these methods for transport through a two-level system that is
subject to periodic driving. The numerical results of all four methods show
good agreement for non-interacting systems in the weak regime. Furthermore, we
have observed that circular light can introduce spin current. We expect these
Floquet quantum transport methods to be useful in studying molecular junctions
exposed to light.
