Speaker: Leonid Fedichkin, Institute for Quantum Sciences & Dept. of Physics and Astronomy, Michigan State University
Abstract: We investigate the dynamics of electron in a chain of coupled semiconductor quantum dots. The electron tunneling in a system is considered in the presence of decoherence. The realization of a full set of basic logic operations, which are necessary for fulfillment of quantum computations, is possible. As the level of quantum noise and the resulting decoherence increase, we observe a crossover from a quantum-coherent oscillatory dynamics to a diffusive classical motion. Quantum measurements performed in coupled quantum dot systems are difficult since the stationary state wave functions is not fully localized on individual qubits. As a result, an instantaneous projective single-qubit measurement gives the state population with an error. We show that this type of errors may be significantly reduced.