The perovskite SrTiO3-LaAlO3 structure has advanced to a model system to investigate the rich electronic phenomena arising at polar interfaces. Using first principles calculations and transport measurements we demonstrate that an additional SrTiO3 capping layer prevents structural and chemical reconstruction at the LaAlO3 surface and triggers the electronic reconstruction at a significantly lower LaAlO3 film thickness than for the uncapped systems. Combined theoretical and experimental evidence (from magnetotransport and ultraviolet photoelectron spectroscopy) suggests two spatially separated sheets with electron and hole carriers, that are as close as 1 nm.
@article{arxiv.0912.4671,
title = {Parallel electron-hole bilayer conductivity from electronic interface reconstruction},
author = {R. Pentcheva and M. Huijben and K. Otte and W. E. Pickett and J. E. Kleibeuker and J. Huijben and H. Boschker and D. Kockmann and W. Siemons and G. Koster and H. J. W. Zandvliet and G. Rijnders and D. H. A. Blank and H. Hilgenkamp and A. Brinkman},
journal= {arXiv preprint arXiv:0912.4671},
year = {2015}
}