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Coherent manipulation of electronic states in a double quantum dot

Toshiaki Hayashi·Toshimasa Fujisawa·Hai-Du Cheong·Yoon-Ha Jeong·Yoshiro Hirayama
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Abstract

We investigate coherent time-evolution of charge states (pseudo-spin 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.

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Toshiaki Hayashi, Toshimasa Fujisawa, Hai-Du Cheong, Yoon-Ha Jeong, Yoshiro Hirayama. 2003-08-19. Coherent manipulation of electronic states in a double quantum dot. https://doi.org/10.1103/physrevlett.91.226804

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