Coupled electron and hole quantum wires

We have investigated the effect of many-body correlations on properties of coupled electron-hole quantum wires using a Singwi-Tosi-Land-Sj\"olander approach. At rₛ=4 the acoustic collective mode traverses the single-electron excitation region as a narrow resonance peak and reemerges in the undamped region on the high-q side of the excitation region. The acoustic collective mode, but not the optic mode, is sensitive to the separation between the wires. For rₛ>2.5 the effective interaction acting between the electrons which is mediated by the heavier holes becomes attractive when the separation between the wires drops to a critical value. For 0.8<~rₛ<~2.5 we detect a charge-density-wave ground state for small wire separations.