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. (C) 2007 Elsevier B.V. All rights reserved.