Polarization dependence of Fano resonances in impurity photoconductivity of quantum wells doped with shallow donors

Abstract

The spectrum of impurity photoabsorption of a heterostructure with quantum wells doped with shallow donors has been calculated in the energy range close to the optical phonon energy. It has been shown that the resonant feature of photoconductivity (Fano resonance) caused by the interaction of electrons with polar optical phonons depends strongly on radiation polarization when the resonance state energy is higher than the energy of the bottom of the second quantum-well subband. This dependence on polarization has been experimentally revealed in the impurity photoconductivity spectrum of the AlGaAs/GaAs heterostructure.