Electron pinball and commensurate orbits in a periodic array of scatterers

Abstract

We have introduced an artificial array of scatterers into a macroscopic two-dimensional conductor nearly devoid of intrinsic defects. This generates pronounced structure in the magnetoresistance, anomalous low-field Hall plateaus, and a quenching of the Hail effect about Z?=0. Our calculations show that the predominant features in the data arise from commensurate classical orbits impaled upon small groups of the imposed scatterers.

Ballistic Transport in Graphene Antidot Lattices

“…In our case the data compares well to hard-wall potential lattices in GaAs, which could be realized in GaAs only at much larger lattice periods [6]. We also compared data for similar carrier densities in the electron and hole regime in Fig.…”

“…The peak belonging to 2R C = a, the fundamental antidot peak, is arXiv:1509.05207v1 [cond-mat.mes-hall] 17 Sep 2015 most pronounced. Additional peaks appearing at lower fields correspond to orbits encircling 2, and 4 antidots [6] (see Fig. 1d), confirming a mean free path which spans several lattice periods.…”

“…Here we show that etching fully encapsulated graphene on the nanoscale is more gentle and the high mobility can be preserved. To this end, we prepared graphene antidot lattices [6] where we observe magnetotransport features stemming from ballistic transport. Due to the short lattice period in our samples we can also explore the boundary between the classical and the quantum transport regime.…”

“…Graphene antidot lattices can help circumventing the problem of the missing band gap in transistor applications [12], and were even predicted to serve as the technological basis for spin qubits [13]. Clearly, for advanced graphene nanodevices, not only the bulk mobility has to be improved, but the nanopatterning has to be optimised.Here we present experiments on graphene antidot lattices [6,14,15] etched into hBN/graphene/hBN heterostructures with lattice periods going down to a = 50 nm. Magnetotransport on those samples shows commensurability features stemming from ballistic orbits around one or several antidots.…”

“…Here we present experiments on graphene antidot lattices [6,14,15] etched into hBN/graphene/hBN heterostructures with lattice periods going down to a = 50 nm. Magnetotransport on those samples shows commensurability features stemming from ballistic orbits around one or several antidots.…”