Electron filmed for first time ever

February 22, 2008
Electron filmed for first time ever

Now it is possible to see a movie of an electron. The movie shows how an electron rides on a light wave after just having been pulled away from an atom. This is the first time an electron has ever been filmed, and the results are presented in the latest issue of Physical Review Letters.

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. With the use of a newly developed technology for generating short pulses from intense laser light, so-called attosecond pulses, scientists at the Lund University Faculty of Engineering in Sweden have managed to capture the electron motion for the first time.

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“It takes about 150 attoseconds for an electron to circle the nucleus of an atom. An attosecond is 10-18 seconds long, or, 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, an assistant professor in atomic physics at the Faculty of Engineering, Lund University. He is one of seven researchers behind the study, which was directed by him and Professor Anne L’Huillier.

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. 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,” explains Johan Mauritsson.

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,” adds Johan 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.

It has been possible to create attosecond pulses for a couple of years now, but not until now has anyone managed to use them to film electron movements, since the attosecond pulses themselves are too weak to take clear pictures.

“By taking several pictures of exactly the same moment in the process, it’s possible to create stronger, but still sharp, images. A precondition is for the process to be repeated in an identical manner, which is the case regarding the movement of an electron in a ray of light. We started with a so-called stroboscope. A stroboscope enables us to ‘freeze’ a periodic movement, like capturing a hummingbird flapping its wings. You then take several pictures when the wings are in the same position, such as at the top, and the picture will turn out clear, despite the rapid motion,” clarifies Johan Mauritsson.

More information: www.atto.fysik.lth.se/

Source: Swedish Research Council

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not rated yet Feb 22, 2008
3 / 5 (1) Feb 22, 2008
How is this "image" any different from what anyone with any interest hasn't already seen with circular wave simulations? This is a true measurement of a true electron? It looks very well defined, but... Why is there a black line through the middle?
3 / 5 (1) Feb 23, 2008
This article does an extremely poor job of describing what the 'image' really is and butchering the word itself. Instead of making things simple it has obfuscated the subject matter completely. You cannot discuss movements of electrons without providing guidance on the Heisenberg uncertainty principle, something the author of this piece was too cowardly to attempt.
1 / 5 (1) Feb 27, 2008
What you see is the target laser ray focused by electron quantum wave formed by excitatation of boson condensate cluster by laser pulse. What we are seeing is the result of many consecutive excitations during strobe period due the strobosocope effect. The interference fringes, show a decreasing spacing when plotted as a function of momentum, so that the IR intensity, can be read directly from the interference pattern.

Currently only the Aether Wave Theory ("AWT") supplies a direct interpretation of quantum wave behavior, which is based on Newtonian mechanics of energy spreading through foam. The vacuum appears as composed from density fluctuations of many underlying particles, which are having a structure and behavior of foam. Therefore it's behaving like common soap foam, which gets more dense under shaking temporarily.

It means, every energy wave spreads like less or more dense blob (density gradient or "particle") through vacuum, from this the particle-wave duality follows. The electron is undulating vacuum during motion, so it's making a density wave around itself by its motion as well. The density blob affects the electron motion conversely, because the electron is just a dense wave packet as well and it follows the places with the most dense vacuum in preference.

Therefore the electron wave interferes with it's own density wave of vacuum foam during motion, which results into quantization of it's momentum. For more detailed explanation search the PhysOrg forum for the "AWT" keyword.
5 / 5 (1) Feb 27, 2008
awt makes no predictions
1 / 5 (1) Feb 28, 2008
For example the existence of strings (spongy density fluctuations, similar to those, which appears inside of condensing supercritical vapor) belongs between predictions of AWT. The same structure structures are expected for both the particles (as the string theory supposes), both the vacuum (as the LQG is considering), i.e. the AWT can be used for conceptual unifications of these theories.

The formation of E8 Lie group structures belongs between predictions of AWT theory as well, because it corresponds the most dense arrangement of Aether fluctuations (kissing hyperspheres geometry). You can met with such geometry at the case of dark matter streaks, which are having the same origin, like the foamy structure of vacuum.

The light spreading through foam has a quite specific attributes as well, the AWT expects the light invariance and Lorentz symmetry violation for both low, both high distance scale/energy density scales. The AWT predicts the way, by which the inflation and brane cosmology can be unified, it predicts the evaporative matter formation from quasars, composition of dark matter and many other concepts.

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