  We investigate a Mach-Zehnder interferometer driven by a time-dependent
voltage. Motivated by recent experiments, we focus on a train of Lorentzian
voltage pulses which we compare to a sinusoidal and a constant voltage. We
discuss the visibilities of Aharonov-Bohm oscillations in the current and in
the noise. For the current, we find a strikingly different behavior in the
driven as compared to the static case for voltage pulses containing multiple
charges. For pulses containing fractional charges, we find a universality at
path-length differences equal to multiples of the spacing between the voltage
pulses. These observations can be explained by the electronic energy
distribution of the driven contact. In the noise oscillations, we find
additional features which are characteristic to time-dependent transport.
Finite electronic temperatures are found to have a qualitatively different
influence on the current and the noise.
