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arXiv · 2002.04307

Demonstration of electron focusing using electronic lenses in low-dimensional system

Chengyu Yan·Michael Pepper·Patrick See·Ian Farrer·David Ritchie·Jonathan Griffiths
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Abstract

We report an all-electric integrable electron focusing lens in n-type GaAs. It is shown that a pronounced focusing peak takes place when the focal point aligns with an on-chip detector. The intensity and full width half maximum (FWHM) of the focusing peak are associated with the collimation of injected electrons. To demonstrate the reported focusing lens can be a useful tool, we investigate characteristic of an asymmetrically gate biased quantum point contact with the assistance of focusing lens. A correlation between the occurrence of conductance anomaly in low conductance regime and increase in FWHM of focusing peak is observed. The correlation is likely due to the electron-electron interaction. The reported electron focusing lens is essential for a more advanced electron optics device.

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Chengyu Yan, Michael Pepper, Patrick See, Ian Farrer, David Ritchie, Jonathan Griffiths. 2020-02-11. Demonstration of electron focusing using electronic lenses in low-dimensional system. https://doi.org/10.1038/s41598-020-59453-x

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