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

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 the characteristic of an asymmetrically gate biased quantum point contact with the assistance of a 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.

SUBMITTER: Yan C

PROVIDER: S-EPMC7018971 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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

Yan Chengyu C Pepper Michael M See Patrick P Farrer Ian I Ritchie David D Griffiths Jonathan J

Scientific reports 20200213 1

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 the characteristic of an asymmetrically gate biased quantum point contact with the assistance of a focusin ...[more]

PMID: 32054961

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