Ground-plane screening of Coulomb interactions in two-dimensional systems: How effectively can one two-dimensional system screen interactions in another?

摘要

The use of a nearby metallic ground-plane to limit the range of the Coulombinteractions between carriers is a useful approach in studying the physics oftwo-dimensional (2D) systems. This approach has been used to study Wignercrystallization of electrons on the surface of liquid helium, and mostrecently, the insulating and metallic states of semiconductor-basedtwo-dimensional systems. In this paper, we perform calculations of thescreening effect of one 2D system on another and show that a 2D system is atleast as effective as a metal in screening Coulomb interactions. We also showthat the recent observation of the reduced effect of the ground-plane when the2D system is in the metallic regime is due to intralayer screening.