Projecting images on curved screens poses a dilemma. The sharper the image, the darker it is, even when using lasers and scanning mirrors. A novel optical approach involving the use of an array of microprojectors now brings brightness and sharpness together for the first time on screens of any curvature. It also allows an increase in projection rates by about 10,000 times.
Action-packed science-fiction movies often feature colorful laser bolts. But what would a real...
Laser physicists in Australia have built a tractor beam that can repel and attract objects,...
Spectroscopic chemical sensing has great promise, but current technologies lack sensitivity and broad spectral coverage. DARPA’s Spectral Combs from UV to THz (SCOUT) program aims to overcome these limitations. The goal is to develop chip-sized, optical frequency combs that accurately identify even tiny traces of dangerous biological and chemical substances several football fields away, DARPA is now soliciting proposals for a solution.
Scientists at EPFL in Switzerland have designed a first-ever experiment for demonstrating quantum entanglement in the macroscopic realm. Unlike other such proposals, the experiment is relatively easy to set up and run with existing semiconductor devices.
At the Vienna Univ. of Technology gold nanoparticles have been coupled to a glass fiber. The particles emit light into the fiber in such a way that it does not travel in both directions, as one would expect. Instead, the light can be directed either to the left or to the right. This became possible by employing the spin-orbit coupling of light, creating a new kind of optical switch that has the potential to revolutionize nanophotonics.
The world’s fiber-optic network spans more than 550,000 miles of undersea cable that transmits Email, Websites and other packets of data between continents, all at the speed of light. A rip or tangle in any part of this network can significantly slow telecommunications around the world. Now, engineers have developed a method that predicts the pattern of coils and tangles that a cable may form when deployed onto a rigid surface.
A rip or tangle in any part of world’s 550,000-mile fiber-optic network can significantly slow telecommunications around the world. Now engineers have developed a method that predicts the pattern of coils and tangles that a cable may form when deployed onto a rigid surface. The research combined laboratory experiments with custom-designed cables, computer-graphics technology used to animate hair in movies, and theoretical analyses.
Commercial devices capable of encrypting information in unbreakable codes exist today, thanks to recent quantum optics advances, especially the generation of photon pairs. Now, an international team is introducing a new method to achieve a different type of photon pair source that fits into the tiny space of a computer chip. The team’s method generates “mixed up” photon pairs from devices that are less than one square millimeter in area.
Confined photons have many potential applications, such as efficient miniature lasers, on-chip information storage, or tiny sensors on pharmaceuticals. Making a structure that can capture photons is difficult, but scientists in the Netherlands have recently devised a new type of resonant cavity inside a photonic crystal that imprisons light in all three dimensions.
Using an optical microstructure and gold nanoparticles, scientists have amplified the interaction of light with DNA to the extent that they can now track interactions between individual DNA molecule segments. In doing so, they have approached the limits of what is physically possible. This optical biosensor for single unlabelled molecules could also be a breakthrough in the development of biochips:
Optical circuits use light instead of electricity, making them faster and more energy-efficient than electrical systems. Scientists in Switzerland have now developed a silicon-based photonic crystal nanocavity to be used as a first building-block for photonic “transistors”. The new device requires record low energy to operate.
The invention of fiber optics revolutionized the way we share information, allowing us to transmit data at volumes and speeds we’d only previously dreamed of. Now, electrical engineering researchers at the Univ. of Alberta are breaking another barrier, designing nano-optical cables small enough to replace the copper wiring on computer chips.
To make a better optical fiber for transmitting laser beams, the first idea that comes to mind is probably not a nice long hydrogen bath. And yet, scientists have known for years that hydrogen can alter the performance of optical fibers, which are often used to transmit or even generate laser light in optical devices. Researchers at NIST have put this hydrogen “cure” to practical use.
With the help of ultracold quantum gas, physicists have achieved a 20-fold amplification of single-photon signals, a step that could aid all-optical data processing efforts. The breakthrough was made with the invention of a new type of optical transistor build from a cloud of rubidium atoms, held just above absolute zero, that is transparent to certain wavelengths of light.
Scientists in the U.K. recently published work that describes how graphene can be wrapped around a silicon wire, or waveguide, and modify the transmission of light through it. These waveguide loops, called “racetrack resonators” because of their shape, could help form a device architecture that would make graphene biochemical sensors a reality.
A new home-grown instrument based on bundles of optical fibers is giving Australian astronomers the first “Google street view” of the cosmos—incredibly detailed views of huge numbers of galaxies. Developed by researchers at the Univ. of Sydney and the Australian Astronomical Observatory, the optical-fiber bundles can sample the light from up to 60 parts of a galaxy, for a dozen galaxies at a time.
Scientists in Belgium have recently fabricated the world’s first randomly deformable optical waveguide. This innovative optical link remains functional for bending radii down to 7 mm, and can be stretched to more than a third of its length. A link like this can be used to interconnect optical components within a stretchable system, just like stretchable electrical interconnections.
Nonlinear optical materials are widely used in laser systems, but they require high light intensity and long propagation to be effective. A team in Germany and Texas has designed a new 400-nm thick nonlinear mirror that delivers frequency-doubled output using input light intensity as small as that of a laser pointer. Compared to traditional nonlinear materials, the new option offers a million times increase in nonlinear optical response.
By fusing together the concepts of active fiber sensors and high-temperature fiber sensors, a team of researchers at the Univ. of Pittsburgh has created an all-optical high-temperature sensor for gas flow measurements that operates at record-setting temperatures above 800 C. The new technology should be ideal for use in deep drilling operations, nuclear reactor cores and outer space.
A team of scientists in Japan and New Zealand have combined lasers, nanotechnology, and neuroscience to develop a new, versatile drug delivery system. The precise timing of a femtosecond laser is used to release dopamine, a neurochemical, that is dysfunctional in Parkinson’s Disease in a controlled and repeatable manner that mimics the natural dynamic release mechanism.
A proposed hybrid quantum processor for a future quantum computer uses trapped atoms as the memory and superconducting qubits as the processor. The concept requires, however, an optical trap that is able to work well with superconductors, which don’t like magnetic fields or high optical power. Joint Quantum Institute scientists believe they’ve developed an effective method for creating these ultra-high transmission optical nanofibers.
Crystal IS has introduced Optan, the first commercial semiconductor based on native aluminum nitride (AIN) substrates. Optan increases detection sensitivity from monitoring of chemicals in pharma manufacturing to drinking water analysis.
With precarious particles called polaritons that straddle the worlds of light and matter, Univ. of Michigan researchers have demonstrated a new, practical and potentially more efficient way to make a coherent laser-like beam. They have made what's believed to be the first polariton laser that is fueled by electrical current as opposed to light, and also works at room temperature, rather than way below zero.
Researchers at the Univ. of Adelaide in South Australia have created a thermometer three times more precise than any existing device, able to measure temperature to 30 billionths of a degree. Using the phenomenon called a “whispering gallery”, which projects sounds, the scientists have designed a crystalline disk that concentrates and reinforces light, allowing them to track a minute difference in speed between red light and green light.
Researchers in Spain have introduced a platform technology based on optical antennas for trapping and controlling light with graphene. Their experiments show that the dramatically squeezed graphene-guided light can be focused and bent, following the fundamental principles of conventional optics. The work opens new opportunities for smaller and faster photonic devices and circuits.
Of all the electricity generated in the U.S., more than quarter is consumed by lighting. In 2010, North Carolina’s RTI International launched a new product, NLite, intended to help alleviate this burden by improving the reflectance performance of power-intensive lighting devices such as luminaires and liquid crystal displays. The technology, based on nanofiber reflectance polymers, won a 2011 R&D 100 Award.
A popular technique for studying single molecules is optical trapping. This is a traditionally delicate process, requiring special equipment, a soundproof room and patience as data collected one molecule at a time. Physicists have now shrunk the technology of an optical trap onto a single chip. Instead of just one molecule at a time, the new device can potentially trap hundreds of molecules at once, reducing month-long experiments to days.
- Page 1