Energy spectrum reconstruction at the edge of a two-dimensional electron system with strong spin-orbit coupling

We experimentally demonstrate the simultaneous reconstruction of the bulk and the edge energy spectra caused by strong spin-orbit interaction, at the two lowest filling factors ?=1 and ?=2 for InxGa1-xAs two-dimensional electron system with x=0.75. The observed reconstruction is of different character at these filling factors: It is characterized by zeroing of the energy gap at the levels crossing point at ?=2, while the reconstruction at ?=1 goes through the coexistence of two ?=1 quantum Hall phases with different spin projections. An analysis indicates a strong influence of many-body interaction on the reconstruction at ?=1.