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arXiv · 2111.05246

Aloof electron probing of in-plane SPV charge distributions on GaAs surfaces

Zilin Chen·Wayne Cheng-Wei Huang·Herman Batelaan
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Abstract

The motion of free electrons moving parallel and above a semiconductor surface can be influenced by shining laser light onto the surface. Here we report strong deflection of aloof electrons by an undoped GaAs surface illuminated with a 633nm laser. The deflecting electric field from the surface photovoltaic charges extends 100 {\mu}m into the vacuum. As surface photovoltage (SPV) is sensitive to the electronic states of the GaAs surface, the aloof electron beam serves as a probe for SPV charge dynamics at the mesoscopic length scale. The observed in-plane SPV charge distribution persists beyond 1 second after the laser beam is blocked. Our work suggests the possibility of writing designed 2D charge patterns on semiconductor surfaces with a scanning laser beam, providing unusual flexibility for electron beam manipulation.

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Zilin Chen, Wayne Cheng-Wei Huang, Herman Batelaan. 2021-11-09. Aloof electron probing of in-plane SPV charge distributions on GaAs surfaces. https://arxiv.org/abs/2111.05246

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