Activated Transport in Magnetic-Field Induced Insulating Phase in Two-Dimensional Electron Gas in InGaAs/InP Heterostructures

Abstract

We report on experiments on low temperature (millikelvin range) activated magnetotransport on low-density two-dimensional electron systems in InGaAs/InΡ for Landau level filling factors 0.25 < v < 0.55. The activation energy increases approximately linearly with decreasing filling factor. The observations are discussed in the light of the formation of the Wigner solid.