Quantum Hall effect at cleaved InSb surfaces and low-temperature annealing effect

The authors have performed low-temperature in-plane magnetotransport measurements on two-dimensional electron systems induced by deposition of Ag at in situ cleaved surfaces of p-type InSb. The quantum Hall effect was observed even at low magnetic fields around 2T. The surface electron density and the electron mobility exhibit strong dependence on the Ag coverage and the annealing temperature in the range of 15–40K. The annealing effect suggests that the surface morphology strongly affects the properties of the two-dimensional electron systems.