Instruments that measure the properties of light, known as spectrometers, are widely used in physical, chemical and biological research. These devices are usually too large to be portable, but Massachusetts Institute of Technology scientists have now shown they can create spectrometers small enough to fit inside a smartphone camera, using tiny semiconductor nanoparticles called quantum dots.
Research led by Michigan State University could someday lead to the development of new and...
Nature loves crystals. Salt, snowflakes and quartz are three examples of crystals—materials...
Physicists have developed a new way to control the transport of electrical currents through high...
The rapid evolution of gadgets has brought us an impressive array of “smart” products from phones to tablets, and now watches and glasses. But they still haven’t broken free from their rigid form. Now scientists are reporting a new step toward bendable electronics. They have developed the first light-emitting, transparent and flexible paper out of environmentally friendly materials via a simple, suction-filtration method.
A team of researchers from Université de Montréal, Polytechnique Montréal and the Centre national de la recherche scientifique in France is the first to succeed in preventing two-dimensional layers of black phosphorus from oxidating. In so doing, they have opened the doors to exploiting their striking properties in a number of electronic and optoelectronic devices.
A revolution is coming in flexible electronic technologies as cheaper, more flexible, organic transistors come on the scene to replace expensive, rigid, silicone-based semiconductors, but not enough is known about how bending in these new thin-film electronic devices will affect their performance, say materials scientists at the Univ. of Massachusetts Amherst.
Researchers at the Univ. of Rochester have shown that defects on an atomically thin semiconductor can produce light-emitting quantum dots. The quantum dots serve as a source of single photons and could be useful for the integration of quantum photonics with solid-state electronics: a combination known as integrated photonics.
Making thin films out of semiconducting materials is analogous to how ice grows on a windowpane: When the conditions are just right, the semiconductor grows in flat crystals that slowly fuse together, eventually forming a continuous film. This process of film deposition is common for traditional semiconductors like silicon or gallium arsenide, but Cornell Univ. scientists are pushing the limits for how thin they can go.
As microchip feature dimensions approach atomic scale, it becomes formidably difficult to measure their size and shape. According to the International Technology Roadmap for Semiconductors, within the next couple of years the typical length of a transistor’s “gate”—its on-off switch—will be less than 20 nanometers (nm, billionths of a meter).
In 2013 James Hone, Wang Fong-Jen Professor of Mechanical Engineering at Columbia Engineering, and colleagues at Columbia demonstrated that they could dramatically improve the performance of graphene—highly conducting two-dimensional (2-D) carbon—by encapsulating it in boron nitride (BN), an insulating material with a similar layered structure.
The editors of R&D Magazine have announced a deadline extension for the 2015 R&D 100 Awards entry process until May 18, 2015. The R&D 100 Awards have a 50 plus year history of awarding the 100 most technologically significant products of the year.
A potentially game-changing breakthrough in artificial photosynthesis has been achieved with the development of a system that can capture carbon dioxide emissions before they are vented into the atmosphere and then, powered by solar energy, convert that carbon dioxide into valuable chemical products, including biodegradable plastics, pharmaceutical drugs and even liquid fuels.
Water is the key component in a Rice Univ. process to reliably create patterns of metallic and semiconducting wires less than 10 nm wide. The technique by the Rice lab of chemist James Tour builds upon its discovery that the meniscus, the curvy surface of water at its edge, can be an effective mask to make nanowires.
Researchers have collaborated in the study of the movement of charges over interfaces of semiconductor materials. The group noticed a new kind of transport phenomenon for charges. In the phenomenon, a pair formed by a negative electron and a positive charge moves onto an interface, after which its “message” is passed on to the other side of the interface, where it is carried on by a similar pair.
The promising new material molybdenum disulfide has an inherent issue that’s steeped in irony. The material’s greatest asset, its monolayer thickness, is also its biggest challenge. Monolayer molybdenum disulfide’s ultra-thin structure is strong, lightweight and flexible, making it a good candidate for many applications, such as high-performance, flexible electronics.
Chemists from Brown Univ. have found a way to make new 2-D, graphene-like semiconducting nanomaterials using an old standby of the semiconductor world: silicon. In a paper published in Nanoletters, the researchers describe methods for making nanoribbons and nanoplates from a compound called silicon telluride. The materials are pure, p-type semiconductors that could be used in a variety of electronic and optical devices.
Univ. of Washington scientists have built a new nanometer-sized laser that is energy efficient, easy to build and compatible with existing electronics. Lasers play essential roles in countless technologies, from medical therapies to metal cutters to electronic gadgets. But to meet modern needs in computation, communications, imaging and sensing, scientists are striving to create ever-smaller laser systems that also consume less energy.
Computer chips, solar cells and other electronic devices have traditionally been based on silicon, the most famous of the semiconductors, that special class of materials whose unique electronic properties can be manipulated to turn electricity on and off the way faucets control the flow of water. There are other semiconductors. Gallium arsenide is one such material and it has certain technical advantages over silicon.
Graphene quantum dots made from coal, introduced in 2013 by the Rice Univ. laboratory of chemist James Tour, can be engineered for specific semiconducting properties in either of two single-step processes. In a new study, Tour and colleagues demonstrated fine control over the graphene-oxide dots’ size-dependent band gap, the property that makes them semiconductors.
A team of Columbia Engineering researchers has invented a technology, full-duplex radio integrated circuits (ICs), that can be implemented in nanoscale CMOS to enable simultaneous transmission and reception at the same frequency in a wireless radio. Up to now, this has been thought to be impossible: transmitters and receivers either work at different times or at the same time but at different frequencies.
Engineers at The Univ. of Texas at Dallas have created semiconductor technology that could make night vision and thermal imaging affordable for everyday use. The engineers created an electronic device in affordable technology that detects electromagnetic waves to create images at nearly 10 THz, which is the highest frequency for electronic devices. The device could make night vision and heat-based imaging affordable.
A superconductor that works at room temperature was long thought impossible, but scientists at the Univ. of Southern California may have discovered a family of materials that could make it reality. The team found that aluminum "superatoms" appear to form Cooper pairs of electrons at temperatures around 100 K. Though 100 K is still pretty chilly, this is an increase compared to bulk aluminum metal.
Graphene shows great promise for future electronics, advanced solar cells, protective coatings and other uses, and combining it with other materials could extend its range even further. Experiments at the SLAC National Accelerator Laboratory looked at the properties of materials that combine graphene with a common type of semiconducting polymer.
A new semiconductor compound is bringing fresh momentum to the field of spintronics, an emerging breed of computing device that may lead to smaller, faster, less power-hungry electronics. Created from a unique low-symmetry crystal structure, the compound is the first to build spintronic properties into a material that's stable at room temperature and easily tailored to a variety of applications.
Anyone who has ever toasted the top of their legs with their laptop or broiled their ear on a cell phone knows that microelectronic devices can give off a lot of heat. These devices contain a multitude of transistors, and although each one produces very little heat individually, their combined thermal output is significant and can damage the device.
Lawrence Berkeley National Laboratory researchers have developed a nano-sized optical antenna that can greatly enhance the spontaneous emission of light from atoms, molecules and semiconductor quantum dots. This advance opens the door to light-emitting diodes (LEDs) that can replace lasers for short-range optical communications, including optical interconnects for microchips, plus a host of other potential applications.
A potential avenue to quantum computing currently generating quite the buzz in the high-tech industry is “valleytronics,” in which information is coded based on the wavelike motion of electrons moving through certain 2-D semiconductors. Now, a promising new pathway to valleytronic technology has been uncovered by researchers with the Lawrence Berkeley National Laboratory.
Researchers in Japan revealed that improvements should soon be expected in the manufacture of transistors that can be used, for example, to make flexible, paper-thin computer screens. The scientists reviewed the latest developments in research on photoactive organic field-effect transistors, devices that incorporate organic semiconductors, amplify weak electronic signals and either emit or receive light.
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