Scientists have been able to manufacture 3-D isotropic metamaterials, but up to now only on a very small scale. Now, in a significant breakthrough, scientists from RIKEN, in collaboration with colleagues in Taiwan, have succeeded in creating a large metamaterial up to 4-mm-square in size that is essentially isotropic, using a type of metamaterial element called a split-ring resonator.
The quest to create artificial “squid skin”—camouflaging metamaterials that can “see” colors and...
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.
There’s a new wave of sound on the horizon carrying with it a broad scope of tantalizing potential applications, including advanced ultrasonic imaging and therapy, and acoustic cloaking, levitation and particle manipulation. Researchers with Lawrence Berkeley National Laboratory have developed a technique for generating acoustic bottles in open air that can bend the paths of sound waves along prescribed convex trajectories.
A new method of building materials using light, developed by researchers at the Univ. of Cambridge, could one day enable technologies that are often considered the realm of science fiction. Although cloaked starships won’t be a reality for quite some time, the technique which researchers have developed for constructing materials with building blocks a few nanometers across can be used to control the way that light flies through them.
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.
The light-warping structures known as metamaterials have a new trick in their ever-expanding repertoire. Researchers at NIST have built a silver, glass and chromium nanostructure that can all but stop visible light cold in one direction while giving it a pass in the other. The device could someday play a role in optical information processing and in novel biosensing devices.
Imagine a material with the same weight and density as aerogel—a material so light it's called “frozen smoke”—but with 10,000 times more stiffness. This material could have a profound impact on the aerospace and automotive industries as well as other applications where lightweight, high-stiffness and high-strength materials are needed.
Optical metamaterials harness clouds of electrons called surface plasmons to manipulate and control light. However, plasmonic devices often use gold or silver, which is incompatible with CMOS manufacturing processes. Purdue Univ. scientists have now developed an ultra-thin crystalline superlattice that instead uses metal-dielectrics. Applied using epitaxy, this “hyperbolic” film could greatly expand applications for metamaterials.
A specially formed material that can provide custom broadband absorption in the infrared can be identified and manufactured using "genetic algorithms," according to Penn State Univ. engineers, who say these metamaterials can shield objects from view by infrared sensors, protect instruments and be manufactured to cover a variety of wavelengths.
New plasmonic metamaterials that operate at high temperatures could radically improve solar cell performance and bring advanced computer data storage technology that uses heat to record information on a magnetic disk. The materials could make it possible to harness clouds of electrons called surface plasmons to manipulate and control light.
Using an acoustic metadevice that can influence the acoustic space and can control any of the ways in which waves travel, engineers have demonstrated, for the first time, that it is possible to dynamically alter the geometry of a 3-D colloidal crystal in real time. The crystals designed in the study, called metamaterials, are artificially structured materials that extend the properties of naturally occurring materials and compounds.
More efficient photovoltaic cells. Improved radar and stealth technology. A new way to recycle waste heat generated by machines into energy. All may be possible due to breakthrough photonics research at the Univ. at Buffalo. The work explores the use of a nanoscale microchip component called a “multilayered waveguide taper array” that improves the chip’s ability to trap and absorb light.
Until now, it has been hard to couple light generation into layered semiconductor systems. Scientists in Austria have recently solved this problem using metamaterials, which are able to manipulate light in the terahertz range due to their special microscopic structure. This represents the first combination of metamaterials and quantum cascade structures.
Researchers at the Harvard Univ. School of Engineering and Applied Sciences are giving man-made materials structural color. Producing structural color is not easy, though; it often requires a material’s molecules to be in a very specific crystalline pattern, like the natural structure of an opal, which reflects a wide array of colors.
An ultra-fast and ultra-small optical switch has been invented that could advance the day when photons replace electrons in the innards of consumer products ranging from cell phones to automobiles. The new optical device can turn on and off trillions of times per second and consists of tiny individual switches made of a metamaterial that uses vanadium dioxide.
Using little more than a few perforated sheets of plastic and a staggering amount of number crunching, Duke Univ. engineers have demonstrated the world’s first 3-D acoustic cloak. The new device reroutes sound waves to create the impression that both the cloak and anything beneath it are not there.
Researchers from Empa and ETH Zurich have succeeded in producing a prototype of a vibration-damping material that could change the world of mechanics. The material of the future is not only able to damp vibrations completely; it can also specifically conduct certain frequencies further.
Ultraviolet light (UV) has not only harmful effects on molecules and biological tissue like human skin but it also can impair the performance of organic solar cells upon long-term exposure. Researchers in Germany have now developed a so-called plasmonic metamaterial which is compatible with solar technology and completely absorbs UV light despite being only 20 nm thin.
A Chinese-U.S. research team is exploring the use of metamaterials to create devices that manipulate sound in versatile and unprecedented ways. In a recently published paper, the team reports a simple design for a device, called an acoustic field rotator, which can twist wave fronts inside it so that they appear to be propagating from another direction.
Univ. of Colorado Boulder scientists have found a creative way to radically improve thermoelectric materials, a finding that could one day lead to the development of improved solar panels and more energy-efficient cooling equipment. The technique, building an array of tiny pillars on top of a sheet of thermoelectric material, represents an entirely new way of attacking a century-old problem.
Researchers in California have made progress in a project to develop fast-blinking light-emitting diode systems for underwater optical communications. They have shown that an artificial metamaterial can improve the “blink speed” of a fluorescent light-emitting dye molecule 76 times faster than normal while increasing brightness 80-fold.
Scientists at Ames Laboratory have demonstrated broadband terahertz (THz) wave generation using metamaterials. The discovery may help develop noninvasive imaging and sensing, and make possible THz-speed information communication, processing and storage.
Inventor Nikola Tesla imagined the technology to transmit energy through thin air almost a century ago, but experimental attempts at the feat have so far resulted in cumbersome devices that only work over very small distances. But now, Duke Univ. researchers have demonstrated the feasibility of wireless power transfer using low-frequency magnetic fields over distances much larger than the size of the transmitter and receiver.
The field of metamaterials has produced structures with unprecedented abilities, including flat lenses, invisibility cloaks and even optical metatronic devices that can manipulate light in the way electronic circuitry manipulates the flow of electrons. Now, the birthplace of the digital computer, ENIAC, is using this technology in the rebirth of analog computing.
Researchers at The Univ. of Texas at Austin have proposed the first design of a cloaking device that uses an external source of energy to significantly broaden its bandwidth of operation. The team has proposed a design for an active cloak that draws energy from a battery, allowing objects to become undetectable to radio sensors over a greater range of frequencies.
The Information Age will get a major upgrade with the arrival of quantum processors faster and more powerful than today’s supercomputers. For the benefits of this new Information Age 2.0 to be fully realized, however, quantum computers will need fast and efficient multi-directional light sources. While quantum technologies remain grist for science fiction, a team of researchers has taken an important step towards efficient light generation.
- Page 1