High-frequency magnetoconductivity of electrons in non-uniform heterostructures

The high-frequency response of electrons in δ-doped heterostructures with long-scale disorder due to non-uniform donor distribution is studied theoretically. The non-local regime of response is considered when the scale of the variation of the energy level is shorter than the mean free path. The linearized kinetic equation for the elastic scattering case together with the electric neutrality condition are solved in the resonant approximation. The obtained modifications of the lineshape of the cyclotron absorption peak and of the Faraday effect appear to be significant under the condition ωclc/vF∼1, where ωc is the cyclotron frequency, lc is the correlation length of disorder, and vF is the Fermi energy. Numerical estimations are performed for the high-mobility AlGaAs/GaAs heterojunction.