We present a set of concrete and realistic ideas for the implementation of a smallscale quantum computer using electron spins in lateral GaAsAlGaAs quantum dots. Initialization is based on leads in the quantum Hall regime with tunable spinpolarization. Readout hinges on spintocharge conversion via spinselective tunneling to or from the leads, followed by measurement of the number of electron charges on the dot via a charge detector. Singlequbit manipulation relies on a microfabricated wire located close to the quantum dot, and twoqubit interactions are controlled via the tunnel barrier connecting the respective quantum dots. Based on these ideas, we have begun a series of experiments in order to demonstrate unitary control and to measure the coherence time of individual electron spins in quantum dots.

Website: http://arxiv.org/abs/quant-ph/0207059