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Dissipative dynamics of coupled quantum dots under quantum measurement

Shi-Hua Ouyang·Chi-Hang Lam·J. Q. You
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Abstract

We have studied the dissipative dynamics of a solid-state qubit with an extra electron confined to either one of two coupled quantum dots. Previous theoretical work based on Bloch-type rate equations gave an unphysical uniform occupation probability of the electron in the quantum dots even for non-identical dots. We show that this is due to neglecting higher order interactions in the analysis. By including higher order terms, we obtain expected asymmetric occupation probabilities for non-identical dots. Our work demonstrates that the high order interaction terms can lead to important qualitative impacts on the operation of the qubit.

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Shi-Hua Ouyang, Chi-Hang Lam, J. Q. You. 2006-12-28. Dissipative dynamics of coupled quantum dots under quantum measurement. https://doi.org/10.1088/0953-8984%2F18%2F50%2F010

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