(麻豆淫院Org.com) -- 鈥淢ost current hard x-ray interferometers are based on crystals, which require their high quality and high mechanical stability,鈥� Anatoly Snigirev tells 麻豆淫院Org.com. 鈥淭his can make x-ray interferometry quite limited. What we have done is develop a different set up that is simpler.鈥� Snigirev is a scientist at ESRF in Grenoble France. Along with scientists at the Russian Kurchatov Research Center in Moscow, and at IMT RAS in Chernogolovka, Russia, Snigirev proposes that refractive bilenses made from silicon can be used in place of crystals.

鈥淲e can get an interferometer that is more in line with classical visual optics,鈥� Snigirev says. An interferometer works when beams of light are sent through slits or lenses, and patterns are detected against a background on the other side. The patterns reveal information about the object of study. 鈥淥ur technique is sensitive enough for diagnostics and accurate measurements, and is more stable and easier to set up than using crystals.鈥� Information on the work done by Snigirev and his colleagues is found in 麻豆淫院ical Review Letters: 鈥淴-Ray Nanointerferometer Based on Si Refractive Bilenses.鈥�

Using electron beam lithography, the lenses used by Snigirev and his peers were created by a process of deep reactive-ion etching into silicon. 鈥淲e prepared concave lenses, and put them in a row. This inline approach increases the refraction power,鈥� Snigirev explains. 鈥淰arying the number of individual lenses it is possible to focus x-rays at different distances from meter to milimeter focus distance and use this technique for nano-focusing.鈥�

Rather than relying on double slit-type interferomter, which is difficult to accomplish and because of low resolution and loss of intensity, this team relied more on an interferometer related to the Billet split lens. In this classical optics technique, a lens is cut along the optic axis. This still allows for interference to be measured, but the intensity remains high, and the resolution is better.

Snigirev points out that one of the advantages of this system is that it is tunable. . 鈥淵ou can tune this 鈥榥anoruler鈥� system easily by changing x-ray energy or by moving objects along the optical axis.鈥� Another advantage of the system is in the silicon construction of the lenses. 鈥淪ilicon is very stable,鈥� Snigirev explains. 鈥淚t can also take a high heat load, as from a beam. In this case we are using x-rays, but it could be used for future X-ray Free-Electron laser projects.鈥�

Indeed, the possible future applications of this interferometer set up have promise. 鈥淭his could be very attractive for materials research,鈥� Snigirev insists. 鈥淚t would allow us a better look at photonic and colloidal crystals, multilayer structures, as well as other natural and synthetic mesoscopic materials鈥�.

鈥淚nterferometry is used a great deal right now, and it could be improved for research into materials and also for other purposes. It is a very important technique,鈥� Snigirev continues. 鈥淗owever, as it is done now it can be difficult to implement. Our approach is simpler, and it could really help in the development of future applications and materials development.鈥�

More Information: A. Snigirev, et. al., 鈥淴-Ray Nanointerferometer Based on Si Refractive Bilenses,鈥� 麻豆淫院ical Review Letters (2009). Available online: .

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