Plasmon-pole approximation for semiconductor quantum-wire electrons

We develop the plasmon-pole approximation for an interacting electron gas confined in a semiconductor quantum wire. We argue that the plasmon-pole approximation becomes a more accurate approach in quantum-wire systems than in higher-dimensional systems because of severe phase-space restrictions on particle-hole excitations in one dimension. As examples, we use the plasmon-pole approximation to calculate the electron self-energy due to the Coulomb interaction and the hot-electron energy relaxation rate due to LO-phonon emission in GaAs quantum wires. We find that the plasmon-pole approximation works extremely well as compared with more complete many-body calculations.