Imaging disorder-induced scattering centers in quantum Hall incompressible strip

While the disorder-induced quantum Hall (QH) effect has been studied previously, the effect of disorder potential on microscopic features of the integer QH effect remains unclear, particularly for the incompressible (IC) strip. In this research, a scanning gate microscope incorporated with the nonequilibrium transport technique is used to image the region of QH IC strip that emerges near the sample edge. It was found that different mobility samples with varying disorder potentials showed the same spatial dependence of the IC strip on the filling factor ($\ensuremath{\nu}$). In the low-mobility sample alone, scattering centers such as bright, dark, and annular patterns, alternately appear within the IC strip. These observed patterns are ascribed to inter-Landau level scattering assisted by resonance tunneling through an impurity bound state. It is concluded that disorder-induced scattering can be effectively detected using the applied technique in a low-mobility sample.