Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Breaking the Barrier Toward Nanometer X-ray Resolution

02.10.2007
Possible advances for nanoscience, energy, biology, and materials research

A team of researchers at the U.S. Department of Energy's Brookhaven National Laboratory have overcome a major obstacle for using refractive lenses to focus x-rays. This method will allow the efficient focusing of x-rays down to extremely small spots and is an important breakthrough in the development of a new, world-leading light source facility that promises advances in nanoscience, energy, biology, and materials research.

At Brookhaven's National Synchrotron Light Source (NSLS), the scientists exceeded a limit on the ability to focus "hard," or high-energy, x-rays known as the "critical angle." Their results are described online in the September 28, 2007, edition of Physical Review Letters.

The critical angle is the maximum angle that light can be deflected, or bent, by a single surface. Imagine a beam of laser light traveling toward a glass lens. Depending on the characteristics of the lens material and the angle at which the beam is pointed, the light can be refracted, that is, transmitted through the lens but deflected. However, when this light approaches the lens at angles less than the critical angle, the beam does not pass through the lens but is instead reflected. This results in a maximum deflection angle for light that passes through the lens.

The maximum deflection angle determines the minimum spot size to which x-rays can be focused. This poses a problem for researchers who are using x-rays to study molecules, atoms, and advanced materials at the nanoscale - on the order of billionths of a meter. Such small subjects require tightly focused beams.

"One measure of the quality of an x-ray optic is how small a focused spot it can make," said NSLS researcher Ken Evans-Lutterodt. "The problem is that nature does not allow a single lens to deflect the x-rays very much. This limits how small of a spot you can create, and this translates to some fuzziness in the image. To get a sharper image, you need a lens that's more able to deflect the x-rays."

In 2003, a trio of Brookhaven researchers - Evans-Lutterodt, Aaron Stein, and James Ablett - were the first to notice the critical angle limit while investigating the properties of a so-called kinoform lens for focusing hard x-rays. This efficient type of refractive lens is similar to those found in lighthouses. The research team proposed a solution to the critical angle problem of a compound kinoform lens, and both the problem and proposed solution were also suggested later by other researchers in the field.

In the current publication, the researchers implemented their idea by creating a compound lens from a series of four kinoform lenses placed one after the other. Using this setup at NSLS beamline X13B, they showed that the critical angle can be surpassed with hard x-rays, while still focusing like a single lens.

"Thanks to the excellent fabrication resources at Brookhaven's Center for Functional Nanomaterials and at Alcatel-Lucent, we are able to fabricate the lenses to the precision required," Stein said.

This is an important step for the National Synchrotron Light Source II (NSLS-II), a state-of-the-art synchrotron facility that will produce x-rays up to 10,000 times brighter than those generated by the current NSLS and could lead to advances such as alternative-energy technologies and new drugs for fighting disease. One of the major goals of the facility is to probe materials and molecules with just one-nanometer resolution - a capability needed to study the intricate mechanisms of chemical and biological systems.

"Without exceeding the critical angle, the refractive lens resolution would be limited to 24 nanometers or more," Ablett said. "Even though in this experiment we just barely exceeded this limit, we've shown that it can be done. This is just the first step."

Next, the researchers will measure the resolution their new lens system produces, and will continue to fabricate and test optics that push further beyond the critical angle, and closer to the one-nanometer benchmark.

"We've broken the barrier, now there's still more work to be done to get down to those small x-ray spots," Evans-Lutterodt said. "Hopefully this will be one of the routes that NSLS-II and others will use."

Natasha Bozovic, from San Jose State University, also collaborated on this research. Funding was provided by the Office of Basic Energy Sciences within the U.S. Department of Energy's Office of Science.

Note to local editors: Kenneth Evans-Lutterodt is a resident of Bridgewater, NJ; Aaron Stein is a resident of South Huntington, NY; and James Ablett is a resident of Middle Island, NY.

Karen McNulty Walsh | EurekAlert!
Further information:
http://www.bnl.gov

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 >>>