Coulomb Drag as a Probe of Coupled Plasmon Modes in Parallel Quantum Wells.

We show theoretically that the Coulomb drag rate between two parallel quasi-two-dimensional electron gases is substantially enhanced by the coupled acoustic and optic plasmon modes of the system at temperatures T ∼ 0.2TF (where TF is the Fermi temperature) for experimentally relevant parameters. The acoustic mode causes a sharp upturn in the scaled drag rate as a function of temperature at T ≈ 0.2TF . Other experimental signatures of plasmondominated drag are a d dependence on the well separation d, and a peak in the drag rate as a function of relative carrier densities at matched Fermi velocities. 73.50.Dn, 73.20.Mf Typeset using REVTEX