Causes of Weak-localization of Electrons on Liquid Helium

We have investigated the dephasing processes in a weak localization (WL) experiment of a two-dimensional electron system on liquid helium. From low-field magnetoconductivity measurements we can separate the damping of WL on the dephasing of electrons due to electron–electron interaction and the motion of the helium vapour atoms. We observe an intermediate regime where both damping mechanisms are of comparable importance and determine the cross-over from one dominant regime to the other.