In a process comparable to squeezing an elephant through a pinhole, researchers at Missouri University of Science and Technology have designed a way to engineer atoms capable of funneling light through ultrasmall channels. Their research is the latest in a series of recent findings related to how light and matter interact at the atomic scale.
Metamaterials are manufactured materials that derive their unusual properties from structure rather than only composition. In the past, to control the optics of metamaterials, researchers used complicated structures including 3D rings and spirals that are difficult to manufacture in large numbers and small sizes. Researchers at Penn State have applied nature-inspired optimization techniques based on genetic algorithms to simplify efforts to shape wavelength dispersion.
Up until now, the invisibility cloaks put forward by scientists have been fairly bulky contraptions—an obvious flaw for those interested in Harry Potter-style applications. However, researchers from the U.S. have now developed a cloak that is just micrometers thick and can hide 3D objects from microwaves in their natural environment, in all directions and from all of the observers’ positions.
Engineering a unique two-dimensional sheet of gold nanoantennas, researchers at Lawrence Berkeley National Laboratory were able to obtain the strongest signal yet of the photonic spin Hall effect, an optical phenomenon of quantum mechanics that could play a prominent role in the future of computing.
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.
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
Wireless communications and optical computing could soon get a significant boost in speed, thanks to “slow light” and specialized metamaterials through which it travels. Researchers have made the first demonstration of rapidly switching on and off “slow light” in specially designed materials at room temperature. This work opens the possibility to design novel, chip-scale, ultrafast devices for applications in terahertz wireless communications and all-optical computing.
To understand the progression of complex diseases such as cancer, scientists have had to tease out the interactions between cells at progressively finer scales—from the behavior of a single tumor cell in the body on down to the activity of that cell’s inner machinery. To foster such discoveries, mechanical engineers at Massachusetts Institute of Technology are designing tools to image and analyze cellular dynamics at the micro- and nanoscale.
The field of metamaterials involves augmenting materials with specially designed patterns, enabling those materials to manipulate electromagnetic waves and fields in previously impossible ways. Now, researchers from the University of Pennsylvania have come up with a theory for moving this phenomenon onto the quantum scale, laying out blueprints for materials where electrons have nearly zero effective mass.
Microscopic metallic cubes, developed by Duke University, could unleash the enormous potential of metamaterials to absorb light, leading to more efficient and cost-effective large-area absorbers for sensor applications or energy-harvesting devices.
A bit reminiscent of the Terminator T-1000, a new material created by Cornell University researchers is so soft that it can flow like a liquid and then, strangely, return to its original shape. Rather than liquid metal, it is a hydrogel, a mesh of organic molecules with many small empty spaces that can absorb water like a sponge. It qualifies as a "metamaterial" with properties not found in nature and may be the first organic metamaterial with mechanical metaproperties.
Using a combination metamaterials and transformation optics, engineers at Penn State University have developed designs for miniaturized optical devices that can be used in chip-based optical integrated circuits, the equivalent of the integrated electronic circuits that make possible computers and cell phones. Controlling light on a microchip could, in the short term, improve optical communications and allow sensing of any substance that interacts with electromagnetic waves.
Researchers at Massachusetts Institute of Technology have fabricated a 3D, lightweight metamaterial lens that focuses radio waves with extreme precision. The concave lens exhibits a property called negative refraction, bending electromagnetic waves in exactly the opposite sense from which a normal concave lens would work.
The first functional "cloaking" device reported by Duke University electrical engineers in 2006 worked like a charm, but it wasn't perfect. Now a member of that laboratory has developed a new design that ties up one of the major loose ends from the original device. These new findings could be important in transforming how light or other waves can be controlled or transmitted.
In waveguides, such as those used in fiber optics, light has a tendency to reflect backwards, interfering with transmission of data. Today’s optical networks keep light from reflecting backward with devices called isolators. To help enable computer chips that operate with light, researchers at the Massachusetts Institute of Technology have invented a new metamaterial prevents electromagnetic waves from reflecting backward.
Over the past two decades, scientists have managed to create artificial materials whose refractive indices are negative: light is bent in the "wrong" direction. These materials might have several technological applications, including cloaking. Recently, a new technique for creating these metamaterials using kinetic inductance shows promise for dramatic miniaturization of future metamaterials systems.
Lawrence Berkeley National Laboratory researchers have created the world's smallest 3D optical cavities with the potential to generate the world's most intense nanolaser beams. By alternating super-thin multiple layers of silver and germanium, the researchers fabricated an "indefinite metamaterial" from which they created their 3D optical cavities.
Over the past five years mathematicians and other scientists have been working on devices that enable invisibility cloaks. Recent work involving a University of Washington mathematician has resulted in a new solution: an amplifier that boosts light, sound, or other waves while hiding them inside an invisible container. Its developers are calling it Schrödinger's hat.
Researchers are edging toward the creation of new optical technologies using "nanostructured metamaterials" capable of ultra-efficient transmission of light, with potential applications including advanced solar cells and quantum computing.
It's not magic, but new materials designed by two Northwestern University researchers seem to exhibit magical properties. Some contract when they should expand, and others expand when they should contract.
Researchers have taken a step toward overcoming a key obstacle in commercializing "hyperbolic metamaterials," structures that could bring optical advances including ultrapowerful microscopes, computers, and solar cells. The researchers have shown how to create the metamaterials without the traditional silver or gold previously required.
Pentamodes, proposed in 1995 by Graeme Milton and Andrej Cherkaev, have until now been purely theoretical. They exist when the mechanical behavior of materials such as gold or water is expressed in terms of compression and shear parameters. Materials experts in Germany have, for the first time, built such a pentamode material, and it’s called a metafluid for a specific reason.
Scientists at the U.S. Department of Energy's Ames Laboratory have designed a method to evaluate different conductors for use in metamaterial structures, which are engineered to exhibit properties not possible in natural materials.
In a recent series of experiments, a Duke University team demonstrated that a metamaterial construct they developed could create holograms—like the images seen on credit or bank cards—in the infrared range of light, something that has not been done before.
Researchers in applied physics have cleared an important hurdle in the development of advanced materials, called metamaterials, that bend light in unusual ways. Working at a scale applicable to infrared light, the Harvard University team has used extremely short and powerful laser pulses to create 3D patterns of tiny silver dots within a material. Those suspended metal dots are essential for building futuristic devices like invisibility cloaks.