Electron-Beam Manipulation of Silicon Dopants in Graphene

TL;DR

This paper demonstrates precise control of silicon atom manipulation in graphene using electron beams, enabling extended atomic-scale engineering with real-time feedback and improved theoretical understanding.

Contribution

It introduces a method for highly controlled, extended manipulation of silicon dopants in graphene with real-time event detection and advanced modeling.

Findings

Manipulation rate comparable to state-of-the-art techniques

Extended control over silicon atom movement in graphene

Enhanced theoretical models accounting for atomic vibrations

Abstract

The direct manipulation of individual atoms in materials using scanning probe microscopy has been a seminal achievement of nanotechnology. Recent advances in imaging resolution and sample stability have made scanning transmission electron microscopy a promising alternative for single-atom manipulation of covalently bound materials. Pioneering experiments using an atomically focused electron beam have demonstrated the directed movement of silicon atoms over a handful of sites within the graphene lattice. Here, we achieve a much greater degree of control, allowing us to precisely move silicon impurities along an extended path, circulating a single hexagon, or back and forth between the two graphene sublattices. Even with manual operation, our manipulation rate is already comparable to the state-of-the-art in any atomically precise technique. We further explore the influence of electron energy on the manipulation rate, supported by improved theoretical modeling taking into account the vibrations of atoms near the impurities, and implement feedback to detect manipulation events in real time. In addition to atomic-level engineering of its structure and properties, graphene also provides an excellent platform for refining the accuracy of quantitative models and for the development of automated manipulation.