High visibility in an electronic Mach–Zehnder interferometer with random phase fluctuations

We present an original method to measure the visibility of interferences in an electronic Mach–Zehnder interferometer in the presence of low frequency phase fluctuations. We studied the visibility of the interferences as a function of the energy and showed a gaussian variation of the decoherence and/or phase averaging at finite energy. This gaussian variation leads to a visibility modulation with a single side lobe.