Mobility of electrons on a helium film capillary condensed on a 2D-grating

Recent developments in the research on two-dimensional electron systems (2DES) show a trend to bring structure in the 2DES and/or reduce the dimensionality. By applying helium films on a substrate with elevations, thick films are created by capillary condensation, with the structure of the elevations imposed on the 2DES. We present the first results of electrons on films above a two-dimensional dielectric grating. The two-dimensional superstructure still allows the use of an overall Corbino arrangement. Thus absolute and accurate values for the mobility of the electrons could be obtained. The measured equilibrium mobility of the electrons at a temperature of 2 K is 0.25 m 2 /Vs, which is one order of magnitude below the value for the mobility on bulk liquid helium, that was expected.