Emission and absorption of confined and interface optical phonons by electrons in the non-linear transport regime of a parabolic quantum wire

Abstract

We present a detailed study of dissipation by electrons in the non-linear transport regime of harmonically confined quantum wires in GaAs/AlAs structures through emission and absorption of confined and interface optical phonons. An applied magnetic field perpendicular to the interfaces is used to modulate the natural harmonic frequencies in order to explore situations in and off resonance with the vibrational modes. Our results show that electrons absorb both confined phonons and interface phonons over wide angles and backwards, at low drift velocities. The emission occurs both forwards and backwards and dominates entirely for high drift velocities. The confined phonons play the dominant role in the dissipation, even for quantum wires inside thin quantum wells and with a magnetic field strength selected to make the harmonic levels in resonance with the AlAs-like interface mode.