Linear collapse of the depolarization shift in very dilute two-dimensional hole gases

摘要

Very dilute two-dimensional hole systems were probed by resonant inelastic light scattering. This extremely high mobility system occurs in AlxGa1-xAs/GaAs quantum wells designed specifically for their light insensitivity. We find that the depolarization shift in intersubband transitions decreases linearly for hole densities below p=6.6x10(10) cm(-2), dropping to zero below p=1x10(10) cm(-2). (C) 2004 American Institute of Physics.