The new procedure is called "scanning transmission electron microscopy" and works by passing an electron beam over a sample and measuring how many electrons interact with the atoms in said sample. Different arrangements of atoms react with the electrons in different ways so the outcome is unique to a particular atomic structure. The team conducts the initial scan which produces a 2D image, and in order to get to the final 3D product, they combine several scans from different angles. The downside of this technique is that multiple scans can potentiality damage the sample.
The research is led by Jianwei (John) Miao, a UCLA professor of physics.
Currently, a method known as X-Ray crystallography is used to map the layout of billions of atoms at a time, but has never been able to pinpoint an atom's exact coordinates. This all encompassing procedure makes identifying a missing atom impossible.
"Our measurements are so precise, and any vibrations -- like a person walking by -- can affect what we measure," said Peter Ercius, a staff scientist at Lawrence Berkeley National Laboratory. The team of UCLA scientists who happened across this discovery now plan to use it in order to study magnetic properties.
[Image Credit: Mary Scott and Jianwei (John) Miao/UCLA]