Herein we discuss the fabrication of ballistic suspended graphene nanostructures supplemented with local gating. Using in-situ current annealing, we show that exceptional high mobilities can be obtained in these devices. A detailed description is given of the fabrication of bottom and different top-gate structures, which enable the realization of complex graphene structures. We have studied the basic building block, the p-n junction in detail, where a striking oscillating pattern was observed, which can be traced back to Fabry-Perot oscillations that are localized in the electronic cavities formed by the local gates. Finally we show some examples how the method can be extended to incorporate multi-terminal junctions or shaped graphene. The structures discussed here enable the access to electron-optics experiments in ballistic graphene.
@article{arxiv.1409.4751,
title = {Fabrication of ballistic suspended graphene with local-gating},
author = {Romain Maurand and Peter Rickhaus and Peter Makk and Samuel Hess and Endre Tovari and Clevin Handschin and Markus Weiss and Christian Schonenberger},
journal= {arXiv preprint arXiv:1409.4751},
year = {2014}
}