High fidelity measurement of singlet-triplet states in a quantum dot

T. Meunier; K-J. Tielrooij; I. T. Vink; F. H. L. Koppens; H. P. Tranitz; W. Wegscheider; L. P. Kouwenhoven; L. M. K. Vandersypen

doi:10.1002/pssb.200671503

arXiv · cond-mat/0612178

High fidelity measurement of singlet-triplet states in a quantum dot

T. Meunier·K-J. Tielrooij·I. T. Vink·F. H. L. Koppens·H. P. Tranitz·W. Wegscheider·L. P. Kouwenhoven·L. M. K. Vandersypen

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Abstract

We demonstrate experimentally a read-out method that distinguishes between two-electron spin states in a quantum dot. This scheme combines the advantages of the two existing mechanisms for spin-to-charge conversion with single-shot charge detection: a large difference in energy between the two states and a large difference in tunnel rate between the states and a reservoir. As a result, a spin measurement fidelity of 97% was achieved, which is much higher than previously reported fidelities.

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T. Meunier, K-J. Tielrooij, I. T. Vink, F. H. L. Koppens, H. P. Tranitz, W. Wegscheider, L. P. Kouwenhoven, L. M. K. Vandersypen. 2006-12-08. High fidelity measurement of singlet-triplet states in a quantum dot. https://doi.org/10.1002/pssb.200671503

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