Asymmetric double 2DEGs As a basis of quantum hall resistance standards

We study growth and magnetotransport properties of Ga(Al)As based asymmetric double two-dimensional electron gases (2DEG) consisting of a quantum well stacked on top of a heterojunction. We show that the electron densities of the two parallel 2DEG channels can be reliably matched by variation of a single growth parameter. Metrological quality of the resistance quantization of the two parallel quantum Hall channels at filling factor 2 is demonstrated.