Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

We observed mixing between two-electron singlet and triplet states in a double quantum dot, caused by interactions with nuclear spins in the host semiconductor. This mixing was suppressed when we applied a small magnetic field or increased the interdot tunnel coupling and thereby the singlet-triplet splitting. Electron transport involving transitions between triplets and singlets in turn polarized the nuclei, resulting in marked bistabilities. We extract from the fluctuating nuclear field a limitation on the time-averaged spin coherence time T \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\begin{array}{l}{\ast}\\2\end{array}\) \end{document} of 25 nanoseconds. Control of the electron-nuclear interaction will therefore be crucial for the coherent manipulation of individual electron spins.

Bibliography

Koppens, F. H. L., Folk, J. A., Elzerman, J. M., Hanson, R., van Beveren, L. H. W., Vink, I. T., Tranitz, H. P., Wegscheider, W., Kouwenhoven, L. P., & Vandersypen, L. M. K. (2005). Control and Detection of Singlet-Triplet Mixing in a Random Nuclear Field. Science, 309(5739), 1346–1350.

Authors 10
  1. F. H. L. Koppens (first)
  2. J. A. Folk (additional)
  3. J. M. Elzerman (additional)
  4. R. Hanson (additional)
  5. L. H. Willems van Beveren (additional)
  6. I. T. Vink (additional)
  7. H. P. Tranitz (additional)
  8. W. Wegscheider (additional)
  9. L. P. Kouwenhoven (additional)
  10. L. M. K. Vandersypen (additional)
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  32. We thank O. N. Jouravlev and Y. Nazarov for developing a model that helped greatly with the physical interpretation of the data; G. Burkard W. A. Coish V. N. Golovach A. C. Johnson D. Loss and C. M. Marcus for fruitful discussions; R. Schouten B. van den Enden and M. van Oossanen for technical assistance; and J. Caro for supporting infrastructure. Supported by the Defense Advanced Research Projects Agency Quantum Information Science and Technology program the Dutch Organization for Fundamental Research on Matter (FOM) the Netherlands Organization for Scientific Research (NWO) the Office of Naval Research Exploratory Research for Advanced Technology and the EU Research Training Network on spintronics.
Dates
Type When
Created 20 years, 1 month ago (July 21, 2005, 8:33 p.m.)
Deposited 1 year, 7 months ago (Jan. 9, 2024, 10:28 p.m.)
Indexed 4 weeks, 1 day ago (Aug. 7, 2025, 4:50 p.m.)
Issued 20 years ago (Aug. 26, 2005)
Published 20 years ago (Aug. 26, 2005)
Published Print 20 years ago (Aug. 26, 2005)
Funders 0

None

@article{Koppens_2005, title={Control and Detection of Singlet-Triplet Mixing in a Random Nuclear Field}, volume={309}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.1113719}, DOI={10.1126/science.1113719}, number={5739}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Koppens, F. H. L. and Folk, J. A. and Elzerman, J. M. and Hanson, R. and van Beveren, L. H. Willems and Vink, I. T. and Tranitz, H. P. and Wegscheider, W. and Kouwenhoven, L. P. and Vandersypen, L. M. K.}, year={2005}, month=aug, pages={1346–1350} }