Coulomb drag between quantum wires in a magnetic field

Momentum transfer between two quasi-one-dimensional electron gases, mediated by the Coulomb interaction, is considered in the presence of a magnetic field normal to the plane of the gases. The lateral confinement is assumed to be parabolic. Impurity scattering (screened) and electron-electron interaction are treated self-consistently within the random-phase approximation. The current response is evaluated from the derived momentum-balance equations, which involve the nonequilibrium electron polarizability, in conjunction with a drifted-temperature model for the polarizability. An applied current driven through either of the gases, whose centers are separated by a distance a, induces a contactless current in the other gas about 10⁵ times smaller and in direct analogy with the zero-magnetic-field observations of Solomon et al. Both the applied and the induced current exhibit Shubnikov--de Haas oscillations. The applied current increases slightly with a and saturates at a finite value. In contrast, the induced current decreases approximately as a^-2 for a much larger than the wire width.