PL spectroscopy of Fermi electrons in regime of the quantum Hall effect

The influence of the interlayer coupling on formation of the quantized Hall phase at the filling factor image was studied in the multilayer GaAs/AlGaAs heterostructures. The disorder broaden Gaussian photoluminescence line due to the localized electrons was found in the quantized Hall phase of the isolated multi-quantum well structure. On the other hand, the quantized Hall phase of the weakly-coupled multilayers emitted an asymmetrical line similar to that one observed in the metallic electron systems. We demonstrated that the observed asymmetry indicates a formation of the Fermi surface in the quantized Hall phase of the multilayer electron system due to the interlayer percolation. A sharp decrease of the single-particle scattering time associated with the extended states on the Fermi surface was observed at the filling factor image.