  In this work we present a theoretical approach to study the effect of an
in-plane (parallel) magnetic field on the microwave-assisted transport
properties of a two-dimensional electron system. Previous experimental
evidences show that microwave-induced resistance oscillations and zero
resistance states are differently affected depending on the experimental
set-up: two magnetic fields (two-axis magnet) or one tilted magnetic field. In
the first case, experiments report a clear quenching of resistance oscillations
and zero resistance states. In a tilted field, one obtains oscillations
displacement and quenching but the latter is unbalanced and less intense. In
our theoretical proposal we explain these results in terms of the
microwave-driven harmonic motion performed by the electronic orbits and how
this motion is increasingly damped by the in-plane field.
