A revolutionary microscope that has produced images in the highest resolution ever obtained has been developed by researchers using microscopic techniques pioneered by academics from the Department of Electronics and Electrical Engineering at the University of Sheffield.

The record-breaking electron microscope, built by researchers at Cornell University in the USA, can produce images at a higher resolution than conventional approaches. It could be used to determine the atomic structure of materials that are normally damaged using existing methods.

The microscope may eventually allow researchers to study 2D materials, such graphene, using unprecedented precision to provide new insights into this burgeoning class of useful materials that have extraordinary physical and electrical properties, and which could revolutionise many modern technologies.

It may also lead to the development of a method that can image individual atoms in 3D objects without damaging the structure by using ‘slow’ low-energy electrons.

Electron imaging is usually conducted using expensive lenses and high-energy electrons that damage many types of material. Alternatively, the Cornell research team recorded electrons that had been scattered through high angles to get around these problems.

Once scattered, the electrons don’t look anything like an image, so the Cornell research team used computational algorithms developed by scientists at the University of Sheffield to work out backwards what the specimen looked like. This is what enabled the microscope to generate the record-breaking high resolution image.

For many years, this backwards calculation, known as the phase problem, was regarded as impossible to solve for a large image.

Professor John Rodenburg from the University of Sheffield’s Department of Electronic and Electrical Engineering, who developed the computational algorithms together with his colleague Andrew Maiden, commented:

“The electron microscope developed by the Cornell research team is the most powerful microscope we’ve ever seen. It is capable of capturing images that have an unprecedented level of detail, which is important because it now paves the way for us to develop new insights into material structure at the atomic scale.

“Such an advanced electron microscope wasn’t possible previously because although the technique we developed here at the University of Sheffield works well for X-ray and light microscopes, in the case of electron microscopy it needs a near-perfect detector to get good enough quality data. Now, due to the advances in detector technology made by the Cornell team, this record-breaking microscope can successfully run the Sheffield algorithm.”

For more information on this story please contact Vicky Sampson - v.sampson@sheffield.ac.uk.