Frictional magnetodrag between spatially separated two-dimensional electron systems: Coulomb versus phonon mediated electron–electron interaction

We study the frictional drag due to Coulomb and phonon mediated electron–electron interaction in a double layer electron system exposed to a perpendicular magnetic field. We calculate the transresistivity as a function of magnetic field, temperature, and inter-layer spacing Λ. We find the strikingly different magnetic field and temperature dependence of the transresistivity for Λ=30 and 200 nm and ascribe this to the weak screening effect at large inter-layer separations.