Transport Studies on GaAs/AlGaAs Two-Dimensional Electron Systems Modulated by Triangular Array of Antidots

Triangular antidot lattices of various periods and aspect ratios are fabricated on high mobility GaAs/AlGaAs two-dimensional electron systems (2DESs), and are characterized by magneto-transport measurements at low temperatures down to 300 mK. Commensurability peaks are generally observed in the magneto-resistivity \rho_xx, and remarkable similarity between d\rho_xy/dB and \rho_xx is found. In samples of relatively large aspect ratio d/a, the Aharonov–Bohm-type oscillations are clearly observed in both \rho_xx and \rho_xy, as well as the quenching of the Hall resistivity \rho_xy in the vicinity of B=0. These observations evince the good quality of our samples, and attest to the adequate preparation for fabricating antidot lattices of a reduced period to realize artificial graphene from GaAs/AlGaAs 2DESs.