Phase separation in two-dimensional electron systems: experimental view (brief review)

Key experimental results on unveiling and studying properties of a multiphase state that arises in two-dimensional electron systems due to the interplay of interelectron interactions and disorder are reviewed. The review is focused on the experimental results obtained with high mobility Si-field effects structures (Si-MOS), in which the interaction effects at low carrier concentrations are most pronounced due to the strong electron–electron interactions, multi-valley spectrum, and the short-range character of the random potential. The reviewed effects of phase separation include features in transport, magnetotransport and thermodynamics. Consideration of a number of experimental results is supplemented with a brief review of their theoretical interpretation.