Single qubit from two coupled quantum dots: An approach to semiconductor quantum computations - art. no. 012302

A scheme to possibly implement the quantum computer is proposed based on th e idea to build up the single qubit from two coupled quantum dots. The spat ial separation of the two logic states of the qubit can greatly reduce the decoherence time, which allows one to perform the coherent quantum logic op erations at a fairly high ratio. Together with the realization of the unive rsal quantum logic grates, and the proper scheme of quantum measurement, th e present proposal can satisfy all the essential criteria for quantum compu ting.