Quasiballistic 1D quantum wires are known to have a conductance of the orderof 2e^2/h, with small sample-to-sample fluctuations. We present a study of thetransconductance G_12 of two Coulomb-coupled quasiballistic wires, i.e., weconsider the Coulomb drag geometry. We show that the fluctuations in G_12differ dramatically from those of the diagonal conductance G_ii: thefluctuations are large, and can even exceed the mean value, thus implying apossible reversal of the induced drag current. We report extensive numericalsimulations elucidating the fluctuations, both for correlated and uncorrelateddisorder. We also present analytic arguments, which fully account for thetrends observed numerically.
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