Coulomb drag effect between Luttinger liquids

The exact solution of the one-dimensional Hubbard model, the supersymmetric $t-J$ model, and the gas of fermions interacting via a $\delta$-function potential is used to calculate the drag current between two parallel quantum wires. The critical exponent for the drag current at low temperatures is obtained by means of the mesoscopic energy spectrum and conformal field theory. For a repulsive interaction between the carriers the drag current is opposite to the driving current, while for attractive potentials the two currents are parallel.