Photonic metamaterials are artificial materials created by precise and extremely fine structuring of conventional media using nanotechnology. However, the properties of metamaterials are usually fixed. Researchers in the U.K. have created an artificial material, a metamaterial, with optical properties that can be controlled by electric signals.
In physics, Luttinger’s theorem states that the number of electrons in a material is the same as the number of electrons in all of its atoms added together. But physicists at the University of Illinois and the University of Pennsylvania found that for copper-containing superconductors, known as cuprates, electrons are not enough to carry the current
Professor Heinrich Jaeger's laboratory at the University of Chicago uses 3D printing to test complex qualities and phenomona of shapes made via computer. One such phenomenon is jamming, in which aggregates of randomly placed particles, including spheres or more complicated shapes, or even molecules, transition from fluid-like to solid-like behavior. Recent analysis shows how the properties of a jammed material can be tuned by changing the shape of the constituent particles.
Researchers from Dresden have discovered a new material that conducts electric currents without loss of power over its edges and remains an insulator in its interior. The material is made out of bismuth cubes packed in a honeycomb motif that is known from the graphene structure. As opposed to graphene, the new material exhibits its peculiar electrical property at room temperature, giving it promise for applications in nanoelectronics.
University of Oregon chemists have synthesized organic molecular structures that move both positive and negative electrical charges—a highly desired but often difficult combination to achieve in current efforts to create highly flexible electronic devices and other new-age technologies.
MEH-PPV is a low-cost polymer that can be integrated with silicon chips, and researchers have sought to use it to convert electricity into laser light for use in photonic devices. However, attempts to do this have failed because the amount of electricity needed to generate laser light in MEH-PPV was so high that it caused the material to degrade. Researchers have recently come up with a low-cost way to enhance MEH-PPV’s ability to confine light, protecting the material.
Touch technology company is working with the London College of Fashion, University of the Arts London to develop wearable electronics that use Peratech's QTC sensors. This years-long research project is exploring the needs base and applications for wearable technology bringing together the expertise of industry and academe in a highly creative way.
Imitating the structural elements found in most sea sponges, researchers in Germany have created a new synthetic hybrid material that is extremely flexible yet has a mineral content of almost 90%. They recreated the sponge’s spicules using natural calcium carbonate and integrated a protein of the sponge. The invention is even more flexible than its natural counterpart.
New optical technologies using "metasurfaces" capable of the ultra-efficient control of light are nearing commercialization. According to Alexander Kildishev, an electrical engineer and professor at Purdue University, the metasurfaces could make possible "planar photonics" devices and optical switches small enough to be integrated into computer chips for information processing and telecommunication
Researchers have successfully created a magnetic soliton—a nanosized, spinning droplet that was first theorized 35 years ago. These solitons have implications for the creation of magnetic, spin-based computers. Solitons are waves, localized in space, that preserve their size and momentum. They were first observed in water. Solitons composed of light have proved useful for long-distance, high-speed information transmission. But droplet solitons had never been observed in a magnetic environment, although scientists believed they could exist there.
Kansas State University civil engineers are developing the right mix to reduce concrete's carbon footprint and make it stronger. Their innovative ingredient: biofuel byproducts.
A research team at the National Institute of Materials Science in Japan has recently developed a gel material which is capable of releasing drugs in response to pressure applied by the patient. Three fingers applying force to the site of the gel produces an effect for up to three days. They built the new drug from two materials already used in pharmaceuticals: a saccharide and a natural component of algae.
Phototransistors are a kind of transistors in which the incident light intensity can modulate the charge-carrier density in the channel. To date, research on organic phototransistors (OPT) has mostly focused on thin-film variants. Now, researchers in South Korea have developed high-performance OPTs that are engineered with nanoscale single-crystalline wires. The breakthrough could enable other types of device miniaturization.
The search for sustainable new materials to store heat captured from the sun for release during the night has led scientists to a high-tech combination of paraffin wax and sand.
Electrons flowing swiftly across the surface of topological insulators are "spin polarized," their spin and momentum locked. This new way to control electron distribution in spintronic devices makes TIs a hot topic in materials science. Now scientists have discovered more surprises: contrary to assumptions, the spin polarization of photoemitted electrons from a topological insulator is wholly determined in three dimensions by the polarization of the incident light beam.
Researchers at the University of Illinois at Urbana-Champaign have devised a dynamic and reversible way to assemble nanoscale structures and have used it to encrypt a Morse code message. The team started with a template of DNA origami―multiple strands of DNA woven into a tile. They “wrote” their message in the DNA template by attaching biotin-bound DNA strands to specific locations on the tiles that would light up as dots or dashes.
In a world first, a team of researchers from Australia, China, and the U.S. has created a super strong metallic composite by harnessing the extraordinary mechanical properties of nanowires. According to the study’s authors, the work has effectively overcome a challenge that has frustrated the world's top scientists and engineers for more than three decades, nicknamed the "valley of death" in nanocomposite design.
Damage to building structural elements, elevators, stairs, and fire protection systems caused by the shaking from a major earthquake can play a critical role in the spread of fire and hamper the ability of occupants to evacuate, and impede fire departments in their emergency response operations. These are among the conclusions of a groundbreaking study of post-earthquake building fire performance conducted in 2012 at the Worcester Polytechnic Institute (WPI).
A team of researchers from the National University of Singapore (NUS) has successfully altered the properties of water, making it corrosive enough to etch diamonds. This strange result was achieved by attaching a layer of graphene on diamond and heated to high temperatures. Water molecules trapped between them become highly corrosive, as opposed to normal water.
For years, researchers have developed thin films of bismuth telluride, which converts heat into electricity or electricity to cooling, on top of gallium arsenide to create cooling devices for electronics. But it was not clear how this could be done because the atomic structures do not appear to be compatible. Researchers from North Carolina State University and RTI International have now solved the mystery.
Germany-based company AMSilk has produced the world’s first competitive man-made spider silk fiber, called Biosteel, which is made entirely from recombinant silk proteins. Biosteel has mechanical properties similar to that of natural spider silk when comparing toughness, a measure indicating the kinetic energy absorbed before the fiber breaks.
A rough, whitish block recovered from an Elizabethan shipwreck may be a sunstone, the fabled crystal believed by some to have helped Vikings and other medieval seafarers navigate the high seas, researchers say. That's because of a property known as birefringence, which splits light beams in a way that can reveal the direction of their source with a high degree of accuracy.
A research group at the University of Toronto has recently described a new technique to improve efficiency in what are called colloidal quantum dot photovoltaics. The method depends on a characteristic of quantum dots: Their light-absorption spectrum can be changed simply by changing the size of quantum dot. By adjusting this property to the infrared portion of the spectrum, efficiency is improved.
Working with microscopic artificial atomic nuclei fabricated on graphene, a collaboration of researchers have imaged the “atomic collapse” states theorized to occur around super-large atomic nuclei. This is the first experimental observation of a quantum mechanical phenomenon that was predicted nearly 70 years ago and holds important implications for the future of graphene-based electronic devices.
Unlike conventional electrical insulators, which do not conduct electricity, topological insulators have the unique property of conducting electricity on their surface, while acting as an insulator inside. In a step toward understanding and exploiting an exotic form of matter that has been sparking excitement for potential applications in a new genre of supercomputers, scientists are reporting the first identification of a naturally occurring topological insulator that was retrieved from an abandoned gold mine in the Czech Republic.