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Cotunneling Spectroscopy in Few-Electron Quantum Dots

D. M. Zumbuhl·C. M. Marcus·M. P. Hanson·A. C. Gossard
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Abstract

Few-electron quantum dots are investigated in the regime of strong tunneling to the leads. Inelastic cotunneling is used to measure the two-electron singlet-triplet splitting above and below a magnetic field driven singlet-triplet transition. Evidence for a non-equilibrium two-electron singlet-triplet Kondo effect is presented. Cotunneling allows orbital correlations and parameters characterizing entanglement of the two-electron singlet ground state to be extracted from dc transport.

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D. M. Zumbuhl, C. M. Marcus, M. P. Hanson, A. C. Gossard. 2004-08-12. Cotunneling Spectroscopy in Few-Electron Quantum Dots. https://doi.org/10.1103/physrevlett.93.256801

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