Electron-electron scattering in quantum wires and its possible suppression due to spin effects

A microscopic picture of electron-electron pair scattering in single mode quantum wires is introduced which includes electron spin. A new source of excess noise for hot carriers is presented. We show that zero magnetic field spin splitting in quantum wires can lead to a dramatic spin-subband dependence of electron-electron scattering, including the possibility of strong suppression. As a consequence extremely long electron coherence lengths and new spin-related phenomena are predicted. Since electron bands in III-V semiconductor quantum wires are in general spin split in zero applied magnetic field, these new transport effects are of general importance.