Whoa! As I always say, “If you let me manipulate individual atoms, I can perform black magic!”
So, I really wanted to read about “A Faster Way to Rearrange Atoms” [1]: “scientists can now rearrange individual impurities (in this case, single phosphorous atoms) in a sheet of graphene by using electron beams to knock them around like croquet balls on a field of grass.”
It sounds so simple: use the electron beam of a Scanning Tunneling Electron Microscope to quickly and accurately push specific atoms around a graphene sheet. The trick is, the “push” in question is a complicated billiard shot.
The MIT researchers report on the theory of these maneuvers [2].
“Controlling the exact atomic structure of materials is an ultimate form of engineering “ ([2],, p.1)
One interesting aspect of their approach is that they control the “dopant” atom by zapping a neighboring Carbon atom, which swaps place with the target atom.
Cool!
There are a lot of variables involved, and, needless to say, I don’t understand the details of the physics, not even a tiny bit.
What I do understand is that (a) the electron beam is fast and scalable (you can have more than one beam) and (b) the “billiards shots” are a complicated, but algorithmic collection of steps. You many need to create a code book for different atoms and substrates,and you may need some clever planning software to string together the best moves, but it all should plug right in to the same STEM technology.
In other words, this could be a technique for literally programming the layout of atoms, one by one.
Sigh me up for some of that stuff!
- Mark Anderson, A Faster Way to Rearrange Atoms Could Lead to Powerful Quantum Sensors, in IEEE Spectrum – Nanclast. 2019. https://spectrum.ieee.org/nanoclast/semiconductors/nanotechnology/a-faster-way-to-rearrange-atoms
- Cong Su, Mukesh Tripathi, Qing-Bo Yan, Zegao Wang, Zihan Zhang, Christoph Hofer, Haozhe Wang, Leonardo Basile, Gang Su, Mingdong Dong, Jannik C. Meyer, Jani Kotakoski, Jing Kong, Juan-Carlos Idrobo, Toma Susi, and Ju Li, Engineering single-atom dynamics with electron irradiation. Science Advances, 5 (5):eaav2252, 2019. http://advances.sciencemag.org/content/5/5/eaav2252.abstract
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