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arXiv · 1103.2895

Spin filling of valley-orbit states in a silicon quantum dot

W. H. Lim·C. H. Yang·F. A. Zwanenburg·A. S. Dzurak
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Abstract

We report the demonstration of a low-disorder silicon metal-oxide-semiconductor (Si MOS) quantum dot containing a tunable number of electrons from zero to N=27. The observed evolution of addition energies with parallel magnetic field reveals the spin filling of electrons into valley-orbit states. We find a splitting of 0.10 meV between the ground and first excited states, consistent with theory and placing a lower bound on the valley splitting. Our results provide optimism for the realization in the near future of spin qubits based on silicon quantum dots.

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W. H. Lim, C. H. Yang, F. A. Zwanenburg, A. S. Dzurak. 2011-07-08. Spin filling of valley-orbit states in a silicon quantum dot. https://doi.org/10.1088/0957-4484%2F22%2F33%2F335704

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