Local transport in a disorder-stabilized correlated insulating phase

We report the experimental realization of a correlated insulating phase in two-dimensional (2D) GaAs∕AlGaAs heterostructures at low electron densities in a limited window of background disorder. This has been achieved at mesoscopic length scales, where the insulating phase is characterized by a universal hopping transport mechanism. Transport in this regime is determined only by the average electron separation, independent of the topology of background disorder. We have discussed this observation in terms of a pinned electron solid ground state, stabilized by the mutual interplay of disorder and Coulomb interaction.