Washington, Feb 23 : Scientists at the Lund University Faculty of Engineering in Sweden have managed to capture the motion of an electron on film for the first time.
The movie shows how an electron rides on a light wave after just having been pulled away from an atom.
Previously, it has been impossible to photograph electrons since their extremely high velocities have produced blurry pictures. In order to capture these rapid events, extremely short flashes of light are necessary, but such flashes were not previously available.
But, with the use of a newly developed technology for generating short pulses from intense laser light, the team of scientists captured the electron on film.
With the aid of another laser these scientists have moreover succeeded in guiding the motion of the electron so that they can capture a collision between an electron and an atom on film.
"We have long been promising the research community that we will be able to use attosecond pulses to film electron motion," said Johan Mauritsson, an assistant professor in atomic physics at the Faculty of Engineering, Lund University.
"Now that we have succeeded, we can study how electrons behave when they collide with various objects, for example. The images can function as corroboration of our theories," he explained.
According to Mauritsson, though the length of the film corresponds to a single oscillation of the light, the speed has then been ratcheted down considerably so that it can be watched.
The filmed sequence shows the energy distribution of the electron and is therefore not a film in the usual sense.
Previously, scientists have studied the movements of electrons using indirect methods, such as by metering their spectrum.
With these methods, it had only been possible to measure the result of an electron's movement, whereas now, with the new technology, the entire event can be monitored.
These scientists also hope to find out more about what happens with the rest of the atom when an inner electron leaves it, for instance how and when the other electrons fill in the gap that is created.
"What we are doing is pure basic research. If there happen to be future applications, they will have to be seen as a bonus," said Mauritsson.