Mach-Zehnder interferometry with periodic voltage pulses

摘要

We investigate a Mach-Zehnder interferometer driven by a time-dependentvoltage. Motivated by recent experiments, we focus on a train of Lorentzianvoltage pulses which we compare to a sinusoidal and a constant voltage. Wediscuss the visibilities of Aharonov-Bohm oscillations in the current and inthe noise. For the current, we find a strikingly different behavior in thedriven as compared to the static case for voltage pulses containing multiplecharges. For pulses containing fractional charges, we find a universality atpath-length differences equal to multiples of the spacing between the voltagepulses. These observations can be explained by the electronic energydistribution of the driven contact. In the noise oscillations, we findadditional features which are characteristic to time-dependent transport.Finite electronic temperatures are found to have a qualitatively differentinfluence on the current and the noise.