Nonlinear dynamics in far-infrared driven quantum-well intersubband transitions

Abstract

We study the effect of many-body interactions on the collective response of confined electrons in doped quantum-well (QW) heterostructures to intense far-infrared radiation. Absorption line shapes are computed both by numerically integrating the equations of motion and by using the appropriately time-averaged equations. For a two-subband double-QW system, optical bistability and period-doubling bifurcations are observed and their parameter range of activity is given. For a three-subband asymmetric triple-QW system driven at $\ensuremath{\omega}\ensuremath{\approx}{E}_{2}\ensuremath{-}{E}_{0},$ Hopf bifurcations occur which generate a strong response at a frequency incommensurate with the drive frequency or any natural frequency of the system.