Cloaking experiments move from microwaves to visible light
On the face of it, the recent computer simulation of optical cloaking using concentric rings of silicon photonic crystals is not the same thing as an actual device. But scientists working on the project say the real thing is almost within reach.
Miniature pulsed laser may be scalpel of the future
It’s one thing to develop a pulsed laser able to destroy harmful cells and tumors with nanoscale precision. It’s another thing to build a 15-mm endoscopic femtosecond laser. A Univ. of Texas at Austin engineer has done so, and plans make it smaller, cheaper, and even disposable.
Quantum images reveal what light doesn’t normally show
For the first time, researchers can easily create quantum images by sending light beams through rubidium gas. The entangled, or paired, images hold information not collected by normal films or camera sensors. Such a technique might be useful for storing patterns of complex or encrypted data.
Lock and load: suspended nanolens reinvents lithography
Microscopic plastic beads in water have been tried as laser focal lenses, but they rarely stay aligned. The solution, Princeton engineers have found, is to trap it against the microchip surface with a second computer-controlled laser, allowing it to move over uneven surfaces while retaining an precise pattern.
Quantum Bell test requires space and time apart
Two photons, an entangled pair, were recently sent through optical fibers from Geneva to Satigny and Jussy, two small Swiss towns 18 km apart, giving researchers enough distance—60 μsecs worth—to perform quantum measurements in just 7.1 μsecs. The test fills a loophole and reinforces the nonlocal nature of quantum correlations.
Nanomirror bends x-rays with 35 nm “venetian blinds”
X-rays are powerful observation tools, and a new MIT-developed nanomirror array, made using interference lithography tool called the “nanoruler”, is probably the best attempt yet at manipulating these waves for use in telescopes and extreme ultraviolet lithography.
Putting the squeeze on light for unheard-of accuracy
Current interferometric gravitational wave detectors are extremely sensitive thanks to laser light. But quantum noise disrupts the beams. Squeezing the light, or reducing amplitude at the expense of phase, for example, offers a solution that researchers say will lead to a new generation of detectors.
Magnetic camera roams our gullets at will
Researchers in Germany, trying to improve on previous esophagol cameras which floated freely down to the stomach, attached a magnet to a new 5 g device. Now, with a small controller, physicians can hold it in the esophagus up to 10 minutes. This innovation could let us say goodbye to uncomfortable endocopies.
Budget quantum key encoder keeps quality up, costs down
Quantum key distribution (QKD) systems, which rely on quantum theory for unbreakable encryption conditions, have been held back by the cost of detectors. A new system from NIST which minimizes the detectors required cuts costs dramatically while maintaining enough bandwidth for webcam-quality video streams protected by QKD.
Artificial retina brings sight to the blind Retinal diseases are a major cause of blindness—tens of millions have been affected. An implantable visual prosthesis is no longer science fiction, however. The two-part device collects data in a spectacle frame, which telemetrically transmits information to electrodes directly attached to undamaged nerve cells.
Quantum computing R&D delivers a more practical logic gate The key part to this device, recently demonstrated by Stanford and UC-Santa Barbara scientists, is an indium arsenide quantum dot, which resides in a semiconducting crystal chip of gallium arsenide drilled with photon-trapping holes. Unlike most previous experiments, this one uses semiconductor manufacturing technologies.
Mid-infrared quantum cascade lasers double in efficiency Short wavelength semiconductor lasers have been in production for decades, but mid-infrared lasers, such as those being looked at for defense applications, are still extremely expensive. Recent efficiency gains at Northwestern’s Center for Quantum Devices, however, show hope for the commercial future of these lasers.
Brazilian weezil carries photonic sophistication on its back Engineers have been racing to build a fully optical integrated circuit (Intel has come close), and the best design option seems to be a crystal modeled after diamond. Nanoscale observations of an iridescent beetle’s chitin structure, however, show that nature may already have the design to beat.
Engineers report first room-temperature semicon T-rays Relying on a commonly used molecular beam epitaxy technique, Harvard scientists have built the first terahertz-range semiconductor laser to be cooled using thermoelectrics rather than expensive cryogenics. T-rays have great promise for many sensing applications.
Robots may profit from the eyes of a fly The eyes of a fly can track small, fast objects beyond the visual resolution limit, which is why designers of autonomous flying vehicles want to adapt this capability. A new fiber optic sensor has been built which emulates the fly’s analog, parallel-processing eye.
Distortion in ultrashort pulsed lasers finally comes into focus Before now, researchers had no way of knowing how much distortion was created by the lenses and optics in a femto- or picosecond pulsed laser. Using interferometric techniques, scientists have created a tool which characterizes pulses in space and time at the focus.
Billion-pulse-per-second laser to elevate extrasolar planet hunting A device known as an optical frequency comb has proven its value in analytical instruments to detect such things as disease markers on human breath. Now, the National Institute of Standards and Technology have adapted this ultra-accurate spectral measurement device to the search for Earth-like planets. The pulse rate is much higher than any previous NIST comb.
Liquefaction is a quick chip fix, say researchers Some researchers are using nano-scale physical properties, such as the surface tension of molten metal, to fix problems that fabrication methods can’t avoid. An electrical engineer at Princeton Univ. uses an excimer laser and a plate guide to eliminate defects by melting and shaping the circuits.
NTT achieves big performance gain on low-power optical memory By moving away from silicon, a Japanese company was able to greatly increase the memory retention time of its newest photonic crystal memory chip. Made of a collusion of indium, gallium, arsenic and phosphorous, the new device holds memory for 150 nanosecs, 60 times the previous retention, while consuming just microwatts of power.
Spectroscopic analysis discovery may transform industry A new anistrophic bond model developed by physicists at North Carolina State Univ. opens access to more details than ever before about how light interacts with the interface where two materials meet. Significantly, say the study’s lead authors, scientists will be able to greatly improve data using nonlinear-optical spectroscopy.
Tracking Speeding Photons Just like human drivers, some photons are faster than others depending on road conditions. Nearly identical materials can make a huge difference to travel time, as discovered by Joint Quantum Institute (JQI), College Park, Md., scientists who built a specialized interferometer that can "stop-watch" individual photons.
The World’s Tiniest Nanophotonic Switch Scientists at IBM, Yorktown Heights, N.Y., have taken another significant advance towards sending information inside a computer chip by using light pulses instead of electrons by building the world's tiniest nanophotonic switch. Its footprint is about 100x smaller than the cross section of a human hair.
Atoms and neutrons face the ultimate identity test Interferometers yield high accuracy and resolution, enough to catch even tiny differences between atoms by exploiting their wave nature. A new Stanford Univ. has boosted the accuracy of interferometric wavefunction measurement of electron charge, or “e”, from 10-20e to 10-28e, a factor of 100 million.
Harnessing the power of terahertz radiation Engineers have successfully demonstrated wires that carry plasmons at frequency from the far-infrared end of the electromagnetic spectrum. According to researchers, terahertz radiation waveguides could be a reality in as little as decade, allowing a big jump transmission speeds.
Head-mountable retinal scanning display relies on MEMS Taking advantage of the human eye’s functionality, Brother’s new device makes use of high-speed low-intensity laser light to project an afterimage through the retina. The effect: an image presented without obstruction, perched in virtual space.
Last Thursday, the R&D Daily made one of its occasional forays into the fast-paced world of semiconductor technology, specifically extreme ultraviolet lithography (EUVL). According to new measurements from the National Institute of Standards and Technology, the photoresists designed for use with this hotly-anticipated new technology are twice as effective is previously thought.
The discrepancy was caused by an older measurement method. Unfortunately, it’s not great news for EUV developers because it strongly indicates existing optics are only half as effective as previously thought.
However, judging from a recent conversations with technical leaders at Cymer, a major U.S. maker of radiation sources for semiconductor lithography, the rolling ball that is EUVL won’t be stopped anytime soon.
Cymer is one of just a few companies at the forefront of a race to develop a viable EUV scanner to replace existing 193 nm argon-fluoride-based devices which now dominate the semiconductor industry. Like other companies, it pushing to design a powerful light source in the about 13 nm wavelength range. So far, it has achieved 25 W of continuous power and intends to break 100 W by year’s end. And, like other companies, it must deal with the intense heat generated by such light and design robust optics which are efficient enough to achieve conversion goals.
Only with adequate conversion efficiency will developers of EUVL be in a position to deliver the performance needed when the market wants it.
It remains to be seen whether EUVL is the new standard in 2012 (the target date for widespread adoption of new scanners). But R&D Magazine will be closely following the progress of this and other technologies aimed at the next-generation of microchips; the push to keep us on the path of that oft-cited economic law of Gordon Moore will continue to surprise us.
