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arXiv · 2111.14498

Three-dimensional description of vibration-assisted electron knock-on damage

Alexandru Chirita·Alexander Markevich·Mukesh Tripathi·Nicholas A. Pike·Matthieu J. Verstraete·Jani Kotakoski·Toma Susi
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Abstract

Elastic knock-on is the main electron irradiation damage mechanism in metals including graphene. Atomic vibrations influence its cross-section, but only the out-of-plane direction has been considered so far in the literature. Here, we present a full three-dimensional theory of knock-on damage including the effect of temperature and vibrations to describe ejection into arbitrary directions. We thus establish a general quantitative description of electron irradiation effects through elastic scattering. Applying our methodology to in-plane jumps of pyridinic nitrogen atoms, we show their observed rates imply much stronger inelastic effects than in pristine graphene.

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Alexandru Chirita, Alexander Markevich, Mukesh Tripathi, Nicholas A. Pike, Matthieu J. Verstraete, Jani Kotakoski, Toma Susi. 2021-11-29. Three-dimensional description of vibration-assisted electron knock-on damage. https://doi.org/10.1103/physrevb.105.235419

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