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arXiv · 1103.0320

Observation of the Kondo Effect in a Spin-3/2 Hole Quantum Dot

O. Klochan·A. P. Micolich·A. R. Hamilton·K. Trunov·D. Reuter·A. D. Wieck
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Abstract

We report the observation of Kondo physics in a spin- 3/2 hole quantum dot. The dot is formed close to pinch-off in a hole quantum wire defined in an undoped AlGaAs/GaAs heterostructure. We clearly observe two distinctive hallmarks of quantum dot Kondo physics. First, the Zeeman spin-splitting of the zero-bias peak in the differential conductance is independent of gate voltage. Second, this splitting is twice as large as the splitting for the lowest one-dimensional subband. We show that the Zeeman splitting of the zero-bias peak is highly-anisotropic, and attribute this to the strong spin-orbit interaction for holes in GaAs.

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O. Klochan, A. P. Micolich, A. R. Hamilton, K. Trunov, D. Reuter, A. D. Wieck. 2011-07-20. Observation of the Kondo Effect in a Spin-3/2 Hole Quantum Dot. https://doi.org/10.1103/physrevlett.107.076805

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