Physicists at Australian National Univ. have engineered a spiral laser beam and used it to create a whirlpool of hybrid light-matter particles called polaritons. The ability to control polariton flows in this way could aid the development of completely novel technology to link conventional electronics with new laser and fiber-based technologies.
Since the 1850s scientists have known that crystalline materials are organized into fourteen different basic lattice structures. However, a team of researchers from Vanderbilt Univ. and Oak Ridge National Laboratory now reports that it has discovered an entirely new form of crystalline order that simultaneously exhibits both crystal and polycrystalline properties, which they describe as "interlaced crystals."
Researchers from North Carolina State Univ. have developed a new way to transfer thin semiconductor films, which are only one atom thick, onto arbitrary substrates, paving the way for flexible computing or photonic devices. The technique is much faster than existing methods and can perfectly transfer the atomic scale thin films from one substrate to others, without causing any cracks.
Researchers from North Carolina State Univ. and Hong Kong Univ. of Science and Technology have found that temperature-controlled aggregation in a family of new semiconducting polymers is the key to creating highly efficient organic solar cells that can be mass produced more cheaply. Their findings also open the door to experimentation with different chemical mixtures that comprise the active layers of the cells.
A new class of low-cost polymer materials, which can carry electric charge with almost no losses despite their seemingly random structure, could lead to flexible electronics and displays which are faster and more efficient.
Researchers in Japan have directly observed and recorded electron flow at 80,000 m/sec in a semiconductor. They did so by combining a new laser pulse light source and a photoemission electron microscope to develop an ultra high-speed microscope that enabled visualization of electrons on a 20 nm and 200 femtosec scale.
When studying extremely fast reactions in ultra-thin materials, two measurements are better than one. A new research tool invented by researchers at Lawrence Livermore National Laboratory (LLNL), Johns Hopkins Univ. and NIST captures information about both temperature and crystal structure during extremely fast reactions in thin-film materials.
Using 3-D printing and novel semiconductors, researchers at Oak Ridge National Laboratory have created a power inverter that could make electric vehicles lighter, more powerful and more efficient. At the core of this development is wide bandgap material made of silicon carbide with qualities superior to standard semiconductor materials.
Researchers at Oak Ridge National Laboratory have obtained the first direct observations of atomic diffusion inside a bulk material. The research, which could be used to give unprecedented insight into the lifespan and properties of new materials, is published in Physical Review Letters.
Two research teams working in the same laboratories in Australia have found distinct solutions to a critical challenge that has held back the realization of super powerful quantum computers. The teams created two types of quantum bits, or "qubits", which are the building blocks for quantum computers, that each process quantum data with an accuracy above 99%. They represent parallel pathways for building a quantum computer in silicon.
It’s a well-known phenomenon in electronics: Shining light on a semiconductor, such as the silicon used in computer chips and solar cells, will make it more conductive. But now researchers have discovered that in a special semiconductor, light can have the opposite effect, making the material less conductive instead. This new mechanism of photoconduction could lead to next-generation excitonic devices.
Researchers in the Netherlands can now, for the first time, remotely control a miniature light source at timescales of 200 trillionths of a second. Physicists have developed a way of remotely controlling the nanoscale light sources at an extremely short timescale. These light sources are needed to be able to transmit quantum information.
Electrical engineers in Germany have demonstrated a new kind of building block for digital integrated circuits. Their experiments show that future computer chips could be based on 3-D arrangements of nanometer-scale magnets instead of transistors. In a 3-D stack of nanomagnets, the researchers have implemented a so-called “majority” logic gate, which could serve as a programmable switch in a digital circuit.
Researchers from the Univ. of Texas at Dallas have created technology that could be the first step toward wearable computers with self-contained power sources or, more immediately, a smartphone that doesn’t die after a few hours of heavy use. This technology taps into the power of a single electron to control energy consumption inside transistors, which are at the core of most modern electronic systems.
A little change in temperature makes a big difference for growing a new generation of hybrid atomic-layer structures, according to scientists. Rice Univ. scientists led the first single-step growth of self-assembled hybrid layers made of two elements that can either be side by side and one-atom thick or stacked atop each other. The structure’s final form can be tuned by changing the growth temperature.
A common complaints about solar power is that solar panels are still too expensive. Efforts at making them more efficient or longer-lasting have been limited. A new method developed in Okinawa could solve the expense problem: A hybrid form of deposition is being used to create perovskite solar cells from a mixture of inexpensive organic and inorganic raw materials, eliminating the need for expensive crystallized silicon.
An international team of physicists has shown that information stored in the nuclear spins of hydrogen isotopes in an organic light-emitting diode (LED) or organic LED can be read out by measuring the electrical current through the device. Unlike previous schemes that only work at ultracold temperatures, this is the first to operate at room temperature, and could be used to create extremely dense and highly energy-efficient memory devices.
Faster, smaller, greener computers, capable of processing information up to 1,000 times faster than currently available models, could be made possible by replacing silicon with materials that can switch back and forth between different electrical states. Recent research in the U.K. show that these phase-change materials have promise in new processors made with chalcogenide glass.
A team of Lawrence Berkeley National Laboratory researchers believes it has uncovered the secret behind the unusual optoelectronic properties of single atomic layers of transition metal dichalcogenide (TMDC) materials, the 2-D semiconductors that hold great promise for nanoelectronic and photonic applications.
Researchers have been trying to increase the efficiency of solid oxide fuel cells by lowering the temperatures at which they run. In a serendipitous finding at Pacific Northwest National Laboratory, researchers have created a new form of strontium-chromium oxide that performs as a semiconductor and also allows oxygen to diffuse easily, a requirement for a solid oxide fuel cell.
Typically a highly conductive material, graphene becomes a semiconductor when prepared as an ultra-narrow ribbon. Recent research has now developed a new method to selectively dope graphene molecules with nitrogen atoms. By seamlessly stringing together doped and undoped graphene pieces, ”heterojunctions” are formed in the nanoribbons, allowing electric current to flow in only one direction when voltage is applied.
Defects damage the ideal properties of many 2-D materials, like carbon-based graphene. Phosphorus just shrugs. That makes it a promising candidate for nanoelectronic applications that require stable properties, according to new research by Rice Univ. theoretical physicist Boris Yakobson and his colleagues.
As a semiconductor material, germanium is superior to silicon. But it is more expensive to process for widespread use in batteries, solar cells, transistors and other applications. Researchers in Missouri have now developed what they call “a simple, one-step method” to grow nanowires of germanium from an aqueous solution. Their process could make it more feasible to use germanium in lithium-ion batteries.
Univ. of Washington researchers have developed what they believe is the thinnest-possible semiconductor, a new class of nanoscale materials made in sheets only three atoms thick. They have demonstrated that two of these single-layer semiconductor materials can be connected in an atomically seamless fashion known as a heterojunction. This result could be the basis for next-generation flexible and transparent computing.
A new argument has just been added to the growing case for graphene being bumped off its pedestal as the next big thing in the high-tech world by the 2-D semiconductors known as MX2 materials. An international collaboration of researchers led by Lawrence Berkeley National Laboratory has reported the first experimental observation of ultrafast charge transfer in photo-excited MX2 materials.