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arXiv · 1712.09031

LO-phonon emission rate of hot electrons from an on-demand single-electron source in a GaAs/AlGaAs heterostructure

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

Using a recently-developed time-of-flight measurement technique with 1 ps time resolution and electron-energy spectroscopy, we developed a method to measure the longitudinal-optical-phonon emission rate of hot electrons travelling along a depleted edge of a quantum Hall bar. A comparison of the experimental results to a single-particle model implies that the main scattering mechanism involves a two-step process via intra-Landau-level transition. We show this scattering can be suppressed by controlling the edge potential profile, and a scattering length > 1 mm can be achieved, allowing the use of this system for scalable single-electron device applications.

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N. Johnson, C. Emary, S. Ryu, H. -S. Sim, P. See, J. D. Fletcher, J. P. Griffiths, G. A. C. Jones, I. Farrer, D. A. Ritchie, M. Pepper, T. J. B. M. Janssen, M. Kataoka. 2017-12-25. LO-phonon emission rate of hot electrons from an on-demand single-electron source in a GaAs/AlGaAs heterostructure. https://doi.org/10.1103/physrevlett.121.137703

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