A modulation-doping approach to control the carrier density of the high-density electron gas at a prototype polar/non-polar oxide interface is presented. It is shown that the carrier density of the electron gas at a GdTiO3/SrTiO3 interface can be reduced by up to 20% from its maximum value (~ 3x10^14 cm^-2) by alloying the GdTiO3 layer with Sr. The Seebeck coefficient of the two-dimensional electron gas increases concurrently with the decrease in its carrier density. The experimental results provide insight into the origin of charge carriers at oxide interfaces exhibiting a polar discontinuity.
@article{arxiv.1208.5711,
title = {Modulation doping to control the high-density electron gas at a polar/non-polar oxide interface},
author = {Tyler A. Cain and Pouya Moetakef and Clayton A. Jackson and Susanne Stemmer},
journal= {arXiv preprint arXiv:1208.5711},
year = {2015}
}
Comments
The article has been accepted by Applied Physics Letters. After it is published, it will be found at: http://apl.aip.org/