Modulation-doped AlGaAs/GaAs heterostructures are utilized extensively in the study of quantum transport in nanostructures, but charge fluctuations associated with remote ionized dopants often produce deleterious effects. Electric field-induced carrier systems offer an attractive alternative if certain challenges can be overcome. We demonstrate a field-effect transistor in which the active channel is locally devoid of modulation-doping, but silicon dopant atoms are retained in the ohmic contact region to facilitate reliable low-resistance contacts. A high quality two-dimensional electron gas is induced by a field-effect and is tunable over a wide range of density. Device design, fabrication, and low temperature (T= 0.3K) transport data are reported.
@article{arxiv.1405.1273,
title = {Field-effect-induced two-dimensional electron gas utilizing modulation doping for improved ohmic contacts},
author = {Sumit Mondal and Geoffrey C. Gardner and John D. Watson and Saeed Fallahi and Amir Yacoby and Michael J. Manfra},
journal= {arXiv preprint arXiv:1405.1273},
year = {2015}
}