In bulk silicon, intervalley electronic interference has been shown to lead to strong oscillations in the exchange coupling between impurity electronic wavefunctions, posing a serious manufacturability problem for proposed quantum computers. Here we show that this problem does not arise in proposed architectures using Si/SiGe quantum dots because of the large in-plane strain in Si quantum wells together with the strong confinement potential typical of heterostructures.
@article{arxiv.cond-mat/0408542,
title = {Exchange in a silicon-based quantum dot quantum computer architecture},
author = {S. N. Coppersmith and Seungwon Lee and Paul von Allmen},
journal= {arXiv preprint arXiv:cond-mat/0408542},
year = {2007}
}