Shortest Light Pulse, 'Superlens' CLEO Topics

The shortest light pulse ever created, a new type of laser that provides 3-D retinal imaging with an emerging method called optical coherence tomography (OCT), and a magnifying "superlens" are just some of the breakthroughs in optics and photonics that scientists from around the world will present in papers during the 2007 Conference on Lasers and Electro-Optics/Quantum Electronics Laser Science Conference (CLEO/QELS), being held May 6-11 at the Baltimore Convention Center.

With more than 1500 talks on cutting-edge optics and photonics research, leading laser science event CLEO/QELS is where more than 5000 researchers and engineers gather each year to present the latest science and engineering of photons and lightwaves, and this year's conference promises not to disappoint with its many noteworthy presentations.

Researchers in Italy have created the shortest light pulse yet -- a single isolated burst of extreme ultraviolet (EUV) light that lasts for only 130 attoseconds, which are billionths of a billionth of a second. (How short is that? 130 attoseconds is to one second as a second is to approximately 243 million years -- roughly the time that has passed since the first dinosaurs walked the Earth.) Aiming a man-made attosecond-scale light pulse on atoms and molecules can trigger new effects in electrons -- responsible for all chemical reactions -- and provide new details on how they work.

Working at Italy's National Laboratory for Ultrafast and Ultraintense Optical Science in Milan (as well as laboratories in Padua and Naples), the researchers believe that their current technique, which involves an intense infrared laser striking a jet of argon or neon gas coupled with optical techniques, will allow them to create even shorter pulses well below 100 attoseconds. These isolated attosecond pulses promise to probe electron phenomena such as "wavepackets" -- specially tailored electron waves inside atoms and molecules that may help scientists use lasers to change the course of chemical reactions for scientific and practical uses, such as controlling the breaking of bonds in complex molecules for medical and pharmaceutical applications. The paper, "Isolated Attosecond Pulses in the Few-Cycle Regime," Sansone et al., will be presented on Thursday, May 10, at 9:30 a.m.

The University of Maryland's Igor Smolyaninov will describe what his group calls a "magnifying superlens" in the paper, "Magnifying Superlens in the Visible Frequency Range," being presented during the six-day conference.

Initially inspired by condensed matter theorist Sir John Pendry's "perfect lens" idea, and drawing upon the Princeton University hyperlens and University of Pennsylvania crystal lens concepts as well as Maryland's previous work, the magnifying superlens uses alternating layers of negative and positive index of refraction metamaterials. In negative-refraction metamaterials, light or other electromagnetic radiation bends in the opposite direction than it would in ordinary matter, making it potentially very useful for focusing images. The new device succeeds in magnifying the object while resolving details as tiny as 70 nm, much smaller than the wavelength of visible light.

Other technological breakthroughs to be discussed at CLEO/QELS 2007 include: the first real-time terahertz imaging system that obtains images from 25 meters away, making it potentially very useful for security applications; a new type of laser for providing high-resolution 3-D images of the retina, which could help ophthalmologists improve diagnoses of many eye diseases; optoelectronic "tweezers" that are simpler to use than ordinary optical tweezers and that could potentially improve studies of biological objects and the construction of nanotech materials; a newly emerging optical design known as a far-field hyperlens, a lens made of metamaterials that aims to increase light's abilities to image and magnify submicroscopic objects, such as the components of biological cells; and a new optical technique that provides high-resolution 3-D images of blood vessels by exploiting the natural light-absorbing properties of the red blood cell molecule, an advance that could aid cancer diagnosis.

The meeting is cosponsored by the Optical Society of America (OSA), the American Physical Society Division of Laser Science (APS-DLS) and the IEEE Lasers & Electro-Optics Society (IEEE/LEOS).

CLEO/QELS 2007 also includes an educational forum, plenary sessions, short courses, tutorials, workshops, an exhibition of more than 350 industry-related businesses, and more. For more information, visit: www.cleoconference.org