Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Jupiter’s „Trojans“ on an Atomic Scale

25.01.2012
The planet Jupiter keeps asteroids on stable orbits – and in a similar way, electrons can be stabilized in their orbit around the atomic nucleus. Calculations carried out at the Vienna University of Technology have now been verified in an experiment.

Planets can orbit a star for billions of years. Electrons circling the atomic nucleus are often visualized as tiny planets. But due to quantum effects, the behavior of atoms usually differs significantly from planetary systems. Austrian and US-American scientists have now succeeded in keeping electrons on planet-like orbits for a long time. This was done using an idea from astronomy: Jupiter stabilizes the orbits of asteroids (the so called “Trojans”), and in a very similar way, the orbits of electrons around the nucleus can be stabilized using an electromagnetic field. The results of this experiment have now been published in the journal “Physical Review Letters”.


Giant Atoms

They are probably the largest atoms on earth: “The diameter of the electronic orbits is several hundredths of a millimeter – an enormous distance on an atomic scale”, says Shuhei Yoshida (Vienna UT). The atoms are even larger than erythrocytes. Yoshida made the calculations at Vienna University of Technology, the experiment was carried out at Rice University in Houston (Texas).

The Electron is not a Planet

The idea that atoms are similar to planetary systems dates back to Niels Bohr: he came up with the first atomic model, in which electrons circle the nucleus in well-defined orbits. This view, however, is now seen to be outdated. In quantum physics, the electron is described as a quantum wave, or a “probability cloud”, that surrounds the atomic nucleus. The location of an electron in the ground state (the lowest possible energy level) is not well defined. Relative to the nucleus, it is situated in all possible directions at the same time. Asking about its “real position” or its orbit just does not make sense. Only if the electron is transferred into a state of higher energy, it can be manipulated in such a way that it moves along orbit-like paths.

Jupiter’s trick – Used for the Atom

Unlike planets, electrons will not keep moving in such an orbit for ever. “Without additional stabilization, the electron-wave would become delocalized after a few cycles”, says Professor Joachim Burgdörfer, head of the Institute for Theoretical Physics at Vienna UT. A simple idea on how to stabilize orbits has been known in astronomy for a long time: the gravity of Jupiter, the heaviest planet in our solar system, stabilizes the orbits of the “Trojans” – thousands of small asteroids. They aggregate around so-called “Lagrange points” on Jupiter’s orbital path. Staying close to these Lagrange points, the asteroids circle the sun together with the planet – with exactly the same orbital velocity, so that the asteroids never collide with Jupiter.

In the experiment, the stabilizing influence of Jupiter’s gravity is substituted by a cleverly designed electromagnetic field. The field oscillates precisely with the frequency corresponding to the orbital period of the electron around the nucleus. It sets the pace for the electron, and that way the electron-wave is kept at a specific point for a long time – much like a large number of asteroids, staying close to Jupiter’s Lagrange points on their orbit around the sun. Quantum physics even allows manipulations which are impossible in a planetary system: using the electromagnetic field, the electron can by shifted into a different orbit – as if the orbit of Jupiter and its asteroids was suddenly shifted to the orbit of Saturn.

Big and Small

The physicists succeeded in creating an atomic miniature version of a solar system and preparing atoms which are remarkably close to the historic Bohr model. In future, the researchers want to prepare atoms in which several electrons move on planetary orbits at the same time. Using such atoms, it should be possible to investigate in greater detail how the quantum-world of tiny objects corresponds to the classical world as we perceive it.

Picture download: http://www.tuwien.ac.at/dle/pr/aktuelles/downloads/2012/trojaner

Original publication: http://link.aps.org/doi/10.1103/PhysRevLett.108.043001

Further information:
Prof. Shuhei Yoshida
Institute for Theoretical Physics
Vienna University of Technology
Wiedner Hauptstraße 8, 1040 Wien
+43-1-58801-13611
shuhei.yoshida@tuwien.ac.at
Prof. Joachim Burgdörfer
Institute for Theoretical Physics
Vienna University of Technology
Wiedner Hauptstraße 8, 1040 Wien
+43-1-58801-13610
burg@concord.itp.tuwien.ac.at

Florian Aigner | EurekAlert!
Further information:
http://www.tuwien.ac.at
http://www.tuwien.ac.at/en/news/news_detail/article/7371/

More articles from Physics and Astronomy:

nachricht Structured light and nanomaterials open new ways to tailor light at the nanoscale
23.04.2018 | Academy of Finland

nachricht On the shape of the 'petal' for the dissipation curve
23.04.2018 | Lobachevsky University

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: BAM@Hannover Messe: innovative 3D printing method for space flight

At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.

Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...

Im Focus: Molecules Brilliantly Illuminated

Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.

Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Quantum Technology for Advanced Imaging – QUILT

24.04.2018 | Information Technology

AWI researchers measure a record concentration of microplastic in arctic sea ice

24.04.2018 | Earth Sciences

Complete skin regeneration system of fish unraveled

24.04.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>