Optical Conductivity of Impurity-Doped Parabolic Quantum Wells in an Applied Electric Field

The optical conductivity of impurity-doped parabolic quantum wells in an applied electric field isinvestigated with the memory-function approach, and the analyticexpression for the optical conductivity is derived. Withcharacteristic parameters pertaining to GaAs/Ga_1-xAl_xAsparabolic quantum wells, the numerical results are presented. Itis shown that, the smaller the well width, the larger the peakintensity of the optical conductivity, and the more asymmetric theshape of the optical conductivity; the optical conductivity ismore sensitive to the electric field, the electric field enhancesthe optical conductivity; when the dimension of the quantum wellincreases, the optical conductivity increases until it reaches amaximum value, and then decreases.