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Zero-bias anomaly and Kondo-assisted quasi-ballistic 2D transport

Arindam Ghosh·Matthew Wright·Christophe Siegert·Michael Pepper·Ian Farrer·Chris Ford·David Ritchie
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Abstract

Nonequilibrium transport measurements in mesoscopic quasi-ballistic 2D electron systems show an enhancement in the differential conductance around the Fermi energy. At very low temperatures, such a zero-bias anomaly splits, leading to a suppression of linear transport at low energies. We also observed a scaling of the nonequilibrium characteristics at low energies which resembles electron scattering by two-state systems, addressed in the framework of two-channel Kondo model. Detailed sample-to-sample reproducibility indicates an intrinsic phenomenon in unconfined 2D systems in the low electron-density regime.

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Arindam Ghosh, Matthew Wright, Christophe Siegert, Michael Pepper, Ian Farrer, Chris Ford, David Ritchie. 2005-06-27. Zero-bias anomaly and Kondo-assisted quasi-ballistic 2D transport. https://doi.org/10.1103/physrevlett.95.066603

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