Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists make iron transparent

09.02.2012
At the high-brilliance synchrotron light source PETRA III, a team of DESY scientists headed by Dr. Ralf Röhlsberger has succeeded in making atomic nuclei transparent with the help of X-ray light.
At the same time they have also discovered a new way to realize an optically controlled light switch that can be used to manipulate light with light, an important ingredient for efficient future quantum computers. The research results are presented in the current edition of the scientific journal “Nature” (DOI: 10.1038/nature10741).

The effect of electromagnetically induced transparency (EIT) is well known from laser physics. With intense laser light of a certain wavelength it is possible to make a non-transparent material transparent for light of another wavelength. This effect is generated by a complex interaction of light with the atomic electron shell. At DESY’s X-ray source PETRA III, the Helmholtz research team of Röhlsberger managed to prove for the first time that this transparency effect also exists for X-ray light, when the X-rays are directed towards atomic nuclei of the Mössbauer isotope iron-57 (which makes up 2% of naturally occurring iron). Quite remarkably, only very low light intensities are needed to observe this effect, in contrast to standard EIT experiments.

How does the experiment work? The scientists positioned two thin layers of iron-57 atoms in an optical cavity, an arrangement of two parallel platinum mirrors that reflect X-ray light multiple times. The two layers of iron-57 atoms, each approximately three nanometres thick, are precisely kept in position between the two platinum mirrors by carbon, which is transparent for X-ray light of the wavelength used.

Multiple images of two objects located between two parallel mirrors illustrate the principle of electromagnetically induced transparency of atomic nuclei: The interaction of x-rays with two layers of iron within such a system of mirrors (an optical resonator) leads to a quantum mechanical superposition state of iron and its mirror images that causes the iron atomic nuclei to appear transparent. Photo: DESY

This kind of sandwich with a total thickness of only 50 nanometres is irradiated under very shallow angles with an extremely thin X-ray beam from the PETRA III synchrotron light source. Within this mirror system, the light is reflected back and forth several times, generating a standing wave, a so-called resonance. When the light wavelength and the distance between both iron layers are just right in proportion, the scientists can see that the iron becomes almost transparent for the X-ray light. In order for this effect to occur, one iron layer must be located exactly in the minimum (node) of the light resonance, the other one exactly in the maximum.

When the layers are shifted within the cavity, the system immediately becomes non-transparent. The scientists attribute this observation to a quantum-optical effect, caused by the interaction of atoms in the iron layers. Unlike single atoms, the atoms in an optical cavity together absorb and radiate in synchrony. In the geometry of this experiment their oscillations mutually cancel each other, as a result of which the system appears to be transparent. In contrast to previous experiments in the optical regime, only few light quanta are necessary to generate this effect.

“Our result of achieving transparency of atomic nuclei is virtually the EIT effect in the atomic nucleus,” Röhlsberger describes the experiments. “Undoubtedly, there is still a long way to go until the first quantum light computer becomes reality. However, with this effect, we are able to perform a completely new class of quantum-optical experiments of highest sensitivity. With the European XFEL X-ray laser, currently being built in Hamburg, there is a real chance to control X-ray light with X-ray light.”

This experiment definitely means considerable technical progress for quantum computing: apart from the basic possibility to make materials transparent with light, the intensity of light is decisive for a future technical realisation as well. Every additional quantum of light produces additional waste heat; this would be reduced by the use of the presently discovered effect.

For the continuation of these experiments and the optimal utilisation of the extremely small X-ray beam size of the highly brilliant X-ray source PETRA III, a new coating facility will be installed at DESY for the production and optimisation of these optical cavities.

The experiments of the DESY scientists also showed another parallel to the EIT effect: the light trapped in the optical cavity only travels with the speed of a few metres per second – normally it is nearly 300 000 kilometres per second. With further experiments, the scientists will clarify how slow the light really becomes under these circumstances, and whether it is possible to use this effect scientifically. A possible application and at the same time an important building block on the way to light-quantum computers is, for example, the storage of information with extremely slow or even stopped light pulses.

Dr. Thomas Zoufal | idw
Further information:
http://www.desy.de/

More articles from Physics and Astronomy:

nachricht Significantly more productivity in USP lasers
06.12.2016 | Fraunhofer-Institut für Lasertechnik ILT

nachricht Shape matters when light meets atom
05.12.2016 | Centre for Quantum Technologies at the National University of Singapore

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: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Predicting unpredictability: Information theory offers new way to read ice cores

07.12.2016 | Earth Sciences

Sea ice hit record lows in November

07.12.2016 | Earth Sciences

New material could lead to erasable and rewriteable optical chips

07.12.2016 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>