Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Physicists make first ‘molecular movie’ of light

14.08.2006
Oxford University, the Lawrence Berkeley Laboratory in California, and the Massachusetts Institute of Technology have together made the first ‘molecular movie’ of the elementary interaction between light and matter, measuring what happens on a microscopic level when light travels though a medium.

The lead author of the study to be published in Nature, Dr Andrea Cavalleri at the Oxford University Department of Physics, said: ‘We’ve all seen how a stick in a pond appears to be at a different angle depending on whether we look at it from outside or inside the water. At a microscopic level, this effect depends on how stiff atomic bonds are and with how much delay atoms and electrons respond when they are placed in the rapidly wiggling electric field of light.

‘If you want to understand the propagation of light at microscopic level, especially in some the complex materials that are of interest for modern opto-electronic applications, you need to make a ‘molecular movie’ of how the atoms and electrons wiggle in the light field. To do so, you need to find a camera with an extremely quick shutter speed – that of a handful of femtoseconds (which is less than one thousandth of a billionth of a second).

‘This very fast timescale can be reached with modern laser technology – but lasers can’t see where the constituents atoms actually are. If you want to see this ‘shape’ of a molecule you need x-rays, but there are currently no x-rays beams with short enough pulses to take snapshots of atomic motions.

‘What we have managed to do is combine ultrafast laser pulses with electron beams in a particle accelerator, deflecting a small slice of the long electron pulse on a separate orbit of the accelerator. Thus, these electrons radiated short enough x-ray pulses to measure elementary atomic motions on the femtosecond timescale. This enabled us to measure the motion of charged atoms on the ultra fast timescale with an accuracy of less than one thousandth of one billionth of a meter. This means we are capable of resolving in time the displacements of atoms by less than one atomic nucleus.

‘This technology can now be applied to other elementary processes at the microscopic level, and we can measure their displacements with unprecedented speed and resolution.’

Barbara Hott | alfa
Further information:
http://www.ox.ac.uk

More articles from Physics and Astronomy:

nachricht Heating quantum matter: A novel view on topology
22.08.2017 | Université libre de Bruxelles

nachricht Engineering team images tiny quasicrystals as they form
18.08.2017 | Cornell 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: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Cholesterol-lowering drugs may fight infectious disease

22.08.2017 | Health and Medicine

Meter-sized single-crystal graphene growth becomes possible

22.08.2017 | Materials Sciences

Repairing damaged hearts with self-healing heart cells

22.08.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>