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The world’s fastest microscope makes its debut

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The attomicroscope is a modified transmission electron microscope, which uses a beam of electrons to image things as small as a few nanometers across (SN: 7/16/08). Like light, electrons can be thought of as waves. These wavelengths, though, are much smaller than those of light. That means an electron beam has a higher resolution than a conventional laser and can detect smaller things, like atoms or clouds of other electrons.

To get their superfast images, Hassan and colleagues used a laser to chop the electron beam into ultrashort pulses. Like the shutter on a camera, those pulses allowed them to capture a new image of the electrons in a sheet of graphene every 625 attoseconds — roughly a thousand times as fast as existing techniques.

Selected attomicroscopy images taken about 1,200 attoseconds apart show how electrons move through graphene under laser illumination. The small black dots represent carbon atoms. Red areas have high electron density, while white and blue areas have lower electron density, compared to graphene without laser illumination.Mohammed Hassan

The microscope can’t capture images of a single electron yet — that would require extremely high spatial resolution. But by stringing the collected images together, scientists created a kind of stop-motion movie that shows how a collection of electrons move through a molecule.

The technique could let researchers watch how a chemical reaction occurs or probe how electrons move through DNA, Hassan says. That information could help scientists craft new materials or personalized medicines.

“With this new tool, we’re trying to build a bridge between what scientists can find in the lab and real-life applications that could have an impact on our daily lives,” he says.

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