The role of piezoeffect in anomalous dependence of the conductivity of AlGaAs/GaAs heterostructure with a two-dimensional electron gas on the distance between contacts

The electric conductivity of the AlGaAs/GaAs heterostructure with two-dimensional electron gas has been experimentally studied in a temperature range of 10–300 K. At low temperatures, electric resistance of the structure exhibited growth when the distance between contacts decreased from 100 to 20 $\mu$m. For explaining this anomalous behavior, numerical simulation of the influence of piezoeffect in the semiconductor on the channel conductivity was carried out, which showed that it is necessary to take into account the crystallographic orientation of the channel and the influence of remote piezoelectric charges on its potential.