Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The world's sharpest X-ray beam shines at DESY

01.10.2013
Researchers of the University of Gottingen substantially increase resolution at DESY's light source PETRA III

The world's sharpest X-ray beam shines at DESY. At the X-ray light source PETRA III, scientists from Göttingen generated a beam with a diameter of barely 5 nanometres – this is ten thousand times thinner than a human hair. This fine beam of X-ray light allows focusing on smallest details.


This is the reconstruction of the two-dimensional focus field. The intensity is color coded.

Credit: Image: University of Göttingen


This is an electron micrograph of the micro lens on the tip of a needle. The lens has a diameter of just two microns (thousandths of a millimeter).

Credit: Image: University of Göttingen

The research groups of Professor Tim Salditt from the Institute of X-ray Physics and of Professor Hans-Ulrich Krebs from the Institute of Materials Physics of the University of Göttingen published their work in the research journal Optics Express.

High-energy (hard) X-ray light cannot be focused as easily as visible light by using a burning glass. "Instead of a common lens, we use a so-called Fresnel lens which consists of several layers," explains co-author Dr. Markus Osterhoff. The central support is a fine tungsten wire with the thickness of only a thousandth of a millimetre. Around the wire, nanometre-thin silicon and tungsten layers are applied in an alternating way.

The physicists then cut a thin slice from the coated wire. "This slice has 50 to 60 silicon and tungsten layers, comparable to growth rings of a tree," explains team member Florian Döring. "And the layer thicknesses have to be extremely precise," adds Christian Eberl. The two PhD students have optimized the different fabrication steps.

The wire slice with a size of only about two thousandths of a millimetre is used as a lens. However, it does not diffract light like a glass lens but scatters it like an optical grid generating a pattern of bright and dark patches. In this case, the thickness of the layers is selected in such a way that the bright areas of the diffraction pattern coincide at the same spot.

The more precise the lens is fabricated, the sharper becomes the X-ray focus. With this method, the physicists obtained an X-ray beam of 4.3 nanometres (millionth of a millimetre) diameter in horizontal direction and 4.7 nanometres diameter in vertical direction. Until recently it was even debated whether fundamental limits of X-ray optics would stand against such small focal widths. The outstanding brilliance of DESY's X-ray light source PETRA III helped to make a usable nano focus possible.

The fine X-ray beam opens up new possibilities for materials science, e.g. the investigation of nano wires to be used in solar cells. "Usually, when investigating the chemical composition of a sample, the beam size limits the sharpness of the image. Before this experiment, this limit was at about 20 nanometers", said DESY researcher Dr. Michael Sprung, responsible scientist for the PETRA measuring station P10, where the experiments are carried out.

As a next step, the scientists want to improve the performance by depositing the layers on ultrathin and extremely uniform glass fibres. Moreover, they plan to scan first nanoscopic structures with their novel ultra-sharp beam. In the future, such a lens should help to create foci of ultimate flux density with free-electron laser (FEL) radiation.

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

Further reports about: DESY PETRA III X-ray beam X-ray light X-ray microscopy light source solar cell

More articles from Physics and Astronomy:

nachricht What happens when we heat the atomic lattice of a magnet all of a sudden?
17.07.2018 | Forschungsverbund Berlin

nachricht Subaru Telescope helps pinpoint origin of ultra-high energy neutrino
16.07.2018 | National Institutes of Natural Sciences

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: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Microscopic trampoline may help create networks of quantum computers

17.07.2018 | Information Technology

In borophene, boundaries are no barrier

17.07.2018 | Materials Sciences

The role of Sodium for the Enhancement of Solar Cells

17.07.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>