Coulomb drag in double-layer electron systems at even-denominator filling factors

An interacting double-layer system, with uniform positive background, is studied at finite temperature in the presence of a strong magnetic field corresponding precisely to $\nu =1/2l$ filling in each layer. By mapping this system to composite fermions in zero field, we investigate the momentum-transfer rate between the layers. As a result of the residual gauge interactions, it turns out that the drag rate is enhanced at low temperatures, varying as $T^{4/3}$ due to transverse gauge exchange while the contribution of Chern-Simons scalar exchange is reduced to $-T^2\ln T$ as is the case of disordered systems.