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arXiv · 1902.11253

Trapping and counting ballistic non-equilibrium electrons

L. Freise·T. Gerster·D. Reifert·T. Weimann·K. Pierz·F. Hohls·N. Ubbelohde
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Abstract

We demonstrate the trapping of electrons propagating ballistically at far-above-equilibrium energies in GaAs/AlGaAs heterostructures in high magnetic field. We find low-loss transport along a gate-modified mesa edge in contrast to an effective decay of excess energy for the loop around a neighboring, mesa-confined node, enabling high-fidelity trapping. Measuring the full counting statistics via single-charge detection yields the trapping (and escape) probabilities of electrons scattered (and excited) within the node. Energetic and arrival-time distributions of captured electron wave packets are characterized by modulating tunnel barrier transmission.

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L. Freise, T. Gerster, D. Reifert, T. Weimann, K. Pierz, F. Hohls, N. Ubbelohde. 2019-02-28. Trapping and counting ballistic non-equilibrium electrons. https://doi.org/10.1103/physrevlett.124.127701

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