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arXiv · 1212.0918

Signatures of Valley Kondo Effect in Si/SiGe Quantum Dots

Mingyun Yuan·R. Joynt·Zhen Yang·Chunyang Tang·D. E. Savage·M. G. Lagally·M. A. Eriksson·A. J. Rimberg
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Abstract

We report measurements consistent with the valley Kondo effect in Si/SiGe quantum dots, evidenced by peaks in the conductance versus source-drain voltage that show strong temperature dependence. The Kondo peaks show unusual behavior in a magnetic field that we interpret as arising from the valley degree of freedom. The interplay of valley and Zeeman splittings is suggested by the presence of side peaks, revealing a zero-field valley splitting between 0.28 to 0.34 meV. A zero-bias conductance peak for non-zero magnetic field, a phenomenon consistent with valley non- conservation in tunneling, is observed in two samples.

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Mingyun Yuan, R. Joynt, Zhen Yang, Chunyang Tang, D. E. Savage, M. G. Lagally, M. A. Eriksson, A. J. Rimberg. 2012-12-05. Signatures of Valley Kondo Effect in Si/SiGe Quantum Dots. https://doi.org/10.1103/physrevb.90.035302

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