Mobility and localization of charge carriers in a quasi-one-dimensional electron system over liquid helium

Abstract

The conductivity and mobility of charge carriers in a quasi-one-dimensional electron system over liquid helium is measured in the temperature range 0.5–1.8 K in confining electric fields up to 2.5 kV/cm. The system of quasi-one-dimensional channels is constructed by using high-quality optical diffraction gratings arranged at a certain height h over liquid helium which fill the grooves of the gratings, thus creating one-dimensional liquid channels. It is shown that the electron mobility decreases with increasing h, the value of the mobility being smaller than the corresponding value for bulk helium. As the temperature decreases, the mobility increases, passes through a peak, and then decreases. The observed effects can be explained by localization of charge carriers in quasi-one-dimensional electron systems.