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arXiv · 1512.02906

Time-of-Flight Measurements of Single-Electron Wave Packets in Quantum-Hall Edge States

M. Kataoka·N. Johnson·C. Emary·P. See·J. P. Griffiths·G. A. C. Jones·I. Farrer·D. A. Ritchie·M. Pepper·T. J. B. M. Janssen
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Abstract

We report time-of-flight measurements on electrons travelling in quantum-Hall edge states. Hot-electron wave packets are emitted one per cycle into edge states formed along a depleted sample boundary. The electron arrival time is detected by driving a detector barrier with a square wave that acts as a shutter. By adding an extra path using a deflection barrier, we measure a delay in the arrival time, from which the edge-state velocity $v$ is deduced. We find that $v$ follows $1/B$ dependence, in good agreement with the $\vec{E} \times \vec{B}$ drift. The edge potential is estimated from the energy-dependence of $v$ using a harmonic approximation.

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M. Kataoka, N. Johnson, C. Emary, P. See, J. P. Griffiths, G. A. C. Jones, I. Farrer, D. A. Ritchie, M. Pepper, T. J. B. M. Janssen. 2015-12-09. Time-of-Flight Measurements of Single-Electron Wave Packets in Quantum-Hall Edge States. https://doi.org/10.1103/physrevlett.116.126803

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