New York: The film shows, in extreme slow motion, a tiny particle riding a wave as it pulls away from an atomic core and its Swedish makers say it is unique. And indeed it is. For the film, by researchers at the Lund University faculty of engineering, captured an electron on film for the first time ever.

In the past, it was impossible to photograph electrons since their extremely high velocities produced blurry pictures. In order to capture these rapid events, extremely short flashes of light are necessary but such flashes were not previously available. With the use of a newly developed technology for generating short pulses from intense laser light, so-called attosecond pulses, the Swedish scientists managed to capture the electron motion.

"It takes about 150 attoseconds for an electron to circle the nucleus of an atom. An attosecond is 10-18 seconds long. Expressed in another way, an attosecond is related to a second as a second is related to the age of the universe," says Johan Mauritsson, one of seven researchers behind the study. The results of the study have been presented in the latest issue of the journal Physical Review Letters.

"We have long been promising the research community that we will be able to use attosecond pulses to film electron motion. Now that we have succeeded, we can study how electrons behave when they collide with various objects," explained Mauritsson. The Swedish scientists also hope to find out more about what happens with the rest of the atom when an inner electron leaves it as well as how and when the other electrons fill 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. The length of the film corresponds to a single oscillation of the light, but the speed has then been ratcheted down considerably so that we can watch it. 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 has only been possible to measure the result of an electron's movement, whereas now we have the opportunity to monitor the entire event.

Source : IANS