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arXiv:cond-mat/0308362 · Physical Review Letters

Coherent Manipulation of Electronic States in a Double Quantum Dot

T. Hayashi, T. Fujisawa, Hai Du Cheong, Y. H. Jeong, Y. Hirayama

Published Nov 26, 2003• 779 citations
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Abstract

We investigate coherent time evolution of charge states (pseudospin qubit) in a semiconductor double quantum dot. This fully tunable qubit is manipulated with a high-speed voltage pulse that controls the energy and decoherence of the system. Coherent oscillations of the qubit are observed for several combinations of many-body ground and excited states of the quantum dots. Possible decoherence mechanisms in the present device are also discussed.

DOI
10.1103/physrevlett.91.226804

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