Additional planned applications include using smart acoustic structures, such as logic gates that can control acoustic waves by altering their propagation, for communication systems in environmental conditions too extreme for conventional electronic devices and photonic structures."
#Researchers Build a Transistor from a Molecule and A few Atoms A team of physicists from the Paul-Drude-Institut für Festkörperelektronik (PDI) and the Freie Universität Berlin (FUB), Germany, the NTT
and the U s. Naval Research Laboratory (NRL), United states, has used a scanning tunneling microscope to create a minute transistor consisting of a single molecule and a small number of atoms.
The observed transistor action is markedly different from the conventionally expected behavior and could be important for future device technologies as well as for fundamental studies of electron transport in molecular nanostructures.
Transistors have a channel region between two external contacts and an electrical gate electrode to modulate the current flow through the channel.
In atomic-scale transistors, this current is extremely sensitive to single electrons hopping via discrete energy levels.
Single-electron transport in molecular transistors has been studied previously using top-down approaches, such as lithography and break junctions.
But atomically precise control of the gate which is crucial to transistor action at the smallest size scales is not possible with these approaches.
The team used a highly stable scanning tunneling microscope (STM) to create a transistor consisting of a single organic molecule and positively charged metal atoms
positioning them with the STM tip on the surface of an indium arsenide (Inas) crystal. Kiyoshi Kanisawa, a physicist at NTT-BRL, used the growth technique of molecular beam epitaxy to prepare this surface.
Subsequently, the STM approach allowed the researchers, first, to assemble electrical gates from the+1 charged atoms with atomic precision and, then,
similar to the working principle of a quantum dot gated by an external electrode. In our case, the charged atoms nearby provide the electrostatic gate potential that regulates the electron flow
But there is a substantial difference between a conventional semiconductor quantum dot comprising typically hundreds or thousands of atoms and the present case of a surface-bound molecule:
and orientational dynamics of the molecule This simple and physically transparent model entirely reproduces the experimentally observed single-molecule transistor characteristics.
The perfection and reproducibility offered by these STM-generated transistors will enable the exploration of elementary processes involving current flow through single molecules at a fundamental level.
which they can lead will be important for integrating molecule-based devices with existing semiconductor technologies.
News and information Agilent technologies and A*STAR's Bioprocessing Technology Institute Collaborate on New Bioanalytical Methodologies July 15th, 2015for faster,
-Legislation/Regulation/Funding/Policy Researchers Build a Transistor from a Molecule and A few Atoms July 14th, 2015world first:
2015nanomedicine Agilent technologies and A*STAR's Bioprocessing Technology Institute Collaborate on New Bioanalytical Methodologies July 15th, 2015nanospheres shield chemo drugs,
2015announcements Agilent technologies and A*STAR's Bioprocessing Technology Institute Collaborate on New Bioanalytical Methodologies July 15th, 2015for faster,
2015globalfoundries Completes Acquisition of IBM Microelectronics Business: Transaction adds differentiating technologies, world-class technologists, and intellectual property July 1st, 2015nei Announces the Issuance of Multiple Patents on Self-Healing & Superhydrophobic Coatings June 30th,
therefore targeting their search at a semiconductor material that is able to both convert sunlight into an electrical charge and split the water, all in one;
a compound of gallium and phosphide that also serves as the basis for specific colored leds.
#UCLA study could lead to a new class of materials for making LEDS: Researchers are first to demonstrate electroluminescence from multilayer molybdenum disulfide Over the last decade, advances in the technology of light-emitting diodes,
or LEDS, have helped to improve the performance of devices ranging from television and computer screens to flashlights.
As the uses for LEDS expand, scientists continue to look for ways to increase their efficiency
while simplifying how they are manufactured. A new study by researchers from the California Nanosystems Institute at UCLA is the first demonstration of electroluminescence from multilayer molybdenum disulfide,
or Mos2, a discovery that could lead to a new class of materials for making LEDS.
With this technique, the multilayer Mos2 semiconductors are at least as efficient as monolayer ones. Duan team is currently moving forward to apply this approach to similar materials,
#An easy, scalable and direct method for synthesizing graphene in silicon microelectronics: Korean researchers grow 4-inch diameter, high-quality, multi-layer graphene on desired silicon substrates,
an important step for harnessing graphene in commercial silicon microelectronics Abstract: In the last decade, graphene has been studied intensively for its unique optical, mechanical, electrical and structural properties.
The one-atom-thick carbon sheets could revolutionize the way electronic devices are manufactured and lead to faster transistors, cheaper solar cells, new types of sensors and more efficient bioelectric sensory devices.
As a potential contact electrode and interconnection material, wafer-scale graphene could be an essential component in microelectronic circuits,
but most graphene fabrication methods are not compatible with silicon microelectronics, thus blocking graphene's leap from potential wonder material to actual profit-maker.
Now researchers from Korea University in Seoul, have developed an easy and microelectronics-compatible method to grow graphene
and have synthesized successfully wafer-scale (four inches in diameter), high-quality, multi-layer graphene on silicon substrates.
which ions are accelerated under an electrical field and smashed into a semiconductor. The impacting ions change the physical, chemical or electrical properties of the semiconductor.
In a paper published this week in the journal Applied Physics Letters, from AIP Publishing,
which takes graphene a step closer to commercial applications in silicon microelectronics.""For integrating graphene into advanced silicon microelectronics, large-area graphene free of wrinkles, tears and residues must be deposited on silicon wafers at low temperatures,
which cannot be achieved with conventional graphene synthesis techniques as they often require high temperatures, "said Jihyun Kim, the team leader and a professor in the Department of Chemical and Biological engineering at Korea University."
"Our work shows that the carbon ion implantation technique has great potential for the direct synthesis of wafer-scale graphene for integrated circuit technologies."
Graphene's unique optical, mechanical and electrical properties have lead to the one-atom-thick form of carbon being heralded as the next generation material for faster, smaller, cheaper and less power-hungry electronics."
"In silicon microelectronics, graphene is a potential contact electrode and an interconnection material linking semiconductor devices to form the desired electrical circuits,
the method is suited not for silicon microelectronics, as chemical vapor deposition would require a high growth temperature above 1,
"Thus, we are motivated to develop a transfer-free method to directly synthesize high quality, multilayer graphene in silicon microelectronics."
a microelectronics-compatible technique normally used to introduce impurities into semiconductors. In the process, carbon ions were accelerated under an electrical field
For example, recent LANP plasmonic research has led to breakthroughs in color-display technology, solar-powered steam production and color sensors that mimic the eye."
Today's most efficient photovoltaic cells use a combination of semiconductors that are made from rare and expensive elements like gallium and indium.
Halas said one way to lower manufacturing costs would be to incorporate high-efficiency light-gathering plasmonic nanostructures with low-cost semiconductors like metal oxides.
"The efficiency of semiconductor-based solar cells can never be extended in this way because of the inherent optical properties of the semiconductors."
where the absorption was concentrated near a metal semiconductor interface.""From this perspective, one can determine the total number of electrons produced,
Each consisted of a plasmonic gold nanowire atop a semiconducting layer of titanium dioxide. In the first setup, the gold sat directly on the semiconductor,
and in the second, a thin layer of pure titanium was placed between the gold and the titanium dioxide.
The first setup created a microelectronic structure called a Schottky barrier and allowed only hot electrons to pass from the gold to the semiconductor.
The second setup allowed all electrons to pass.""The experiment clearly showed that some electrons are hotter than others,
including medicine, electronics and energy. Discovered only 11 years ago, graphene is one of the strongest materials in the world, highly conductive, flexible, and transparent.
#Researchers boost wireless power transfer with magnetic field enhancement Wireless power transfer works by having a transmitter coil generate a magnetic field;
a receiver coil then draws energy from that magnetic field. One of the major roadblocks for development of marketable wireless power transfer technologies is achieving high efficiency."
By placing the MRFE between the transmitter and the receiver (without touching either) as an intermediate material,
"We realized that any enhancement needs to not only increase the magnetic field the receiver'sees, 'but also not siphon off any of the power being put out by the transmitter,
"Ricketts says.""The MRFE amplifies the magnetic field while removing very little power from the system."
as well as capacitors whose energy storage capacity increases about tenfold when the fibers are stretched. Fibers and cables derived from the invention might one day be used as interconnects for super-elastic electronic circuits;
robots and exoskeletons having great reach; morphing aircraft; giant-range strain sensors; failure-free pacemaker leads;
and super-stretchy charger cords for electronic devices. In a study published in the July 24 issue of the journal Science,
the scientists describe how they constructed the fibers by wrapping lighter-than-air, electrically conductive sheets of tiny carbon nanotubes to form a jellyroll-like sheath around a long rubber core.
the researchers made strain sensors and artificial muscles in which the buckled nanotube sheaths serve as electrodes
and the thin rubber layer is a dielectric, resulting in a fiber capacitor. These fiber capacitors exhibited a capacitance change of 860 percent
when the fiber was stretched 950 percent.""No presently available material-based strain sensor can operate over nearly as large a strain range,
"Liu said. Adding twist to these double-sheath fibers resulted in fast, electrically powered torsional
--or rotating--artificial muscles that could be used to rotate mirrors in optical circuits or pump liquids in miniature devices used for chemical analysis,
The researchers report in Nano Letters that by combining inorganic semiconductor nanocrystals with organic molecules, they have succeeded in"upconverting"photons in the visible and near-infrared regions of the solar spectrum."
In their experiments, Bardeen and Tang worked with cadmium selenide and lead selenide semiconductor nanocrystals.
"The key to this research is the hybrid composite material--combining inorganic semiconductor nanoparticles with organic compounds.
"Besides solar energy, the ability to upconvert two low energy photons into one high energy photon has potential applications in biological imaging, data storage and organic light-emitting diodes.
and industries, including laser, solar cells, production of transistors and nanomedicine. The colloid form of these particles have very interesting properties and characteristics,
electronics and photonics after passing the required tests and obtaining mass-production of these nanoparticles.
In this context, recently, researchers at the Department of Environmental and Life sciences at Toyohashi Tech have developed a practical magnetic metallic contaminant detector using three high-Tc RF superconducting quantum interference devices
The detection technique is based on recording the remnant magnetic field of a contaminant using SQUID sensors.
SQUID is a high-sensitivity magnetic sensor based on the superconductivity phenomenon. In the process, a strong magnetic field is applied to food to magnetize the metal fragments inside,
can be detected by sensing their magnetic fields using SQUID sensors. This method is advantageous in the sense that it is both safe
the sensor is placed inside a square metallic box designed such that food can be tested as it passes through this box.
Thus, magnetic fields around the sensor are concentrated in the walls of this box.""In experiments, the developed system was able to clearly detect a steel ball with a diameter as small as 0. 3 mm.
#Meet the high-performance single-molecule diode: Major milestone in molecular electronics scored by Berkeley Lab and Columbia University team"Using a single symmetric molecule, an ionic solution and two gold electrodes of dramatically different exposed surface areas,
we were able to create a diode that resulted in a rectification ratio, the ratio of forward to reverse current at fixed voltage, in excess of 200,
which is a record for single-molecule devices, "says Jeff Neaton, Director of the Molecular Foundry, a senior faculty scientist with Berkeley Lab's Materials sciences Division and the Department of physics at the University of California Berkeley,
"The asymmetry necessary for diode behavior originates with the different exposed electrode areas and the ionic solution,
"This leads to different electrostatic environments surrounding the two electrodes and superlative single-molecule device behavior."
"With"smaller and faster"as the driving mantra of the electronics industry, single-molecule devices represent the ultimate limit in electronic miniaturization.
Since then, development of functional single-molecule electronic devices has been a major pursuit with diodes-one of the most widely used electronic components-being at the top of the list.
A typical diode consists of a silicon p-n junction between a pair of electrodes (anode and cathode) that serves as the"valve"of an electrical circuit,
Scientists have fashioned previously single-molecule diodes either through the chemical synthesis of special asymmetric molecules that are analogous to a p-n junction;
or through the use of symmetric molecules with different metals as the two electrodes. However, the resulting asymmetric junctions yielded low rectification ratios,
"The efficiency of the tunneling process depends intimately on the degree of alignment of the molecule's discrete energy levels with the electrode's continuous spectrum.
and Zhenfei Liu to understand the diode behavior quantitatively.""In collaboration with Columbia University's Latha Venkataraman and Luis Campos and their respective research groups, Neaton and Liu fabricated a high-performing rectifier from junctions made of symmetric molecules with molecular resonance
in nearly perfect alignment with the Fermi electron energy levels of the gold electrodes. Symmetry was broken by a substantial difference in the size of the area on each gold electrode that was exposed to the ionic solution.
Owing to the asymmetric electrode area, the ionic solution, and the junction energy level alignment, a positive voltage increases current substantially;
a negative voltage suppresses it equally significantly.""The ionic solution, combined with the asymmetry in electrode areas, allows us to control the junction's electrostatic environment simply by changing the bias polarity,
"Neaton says.""In addition to breaking symmetry, double layers formed by ionic solution also generate dipole differences at the two electrodes,
which is the underlying reason behind the asymmetric shift of molecular resonance. The Columbia group's experiments showed that with the same molecule and electrode setup,
a nonionic solution yields no rectification at all.""The Berkeley Lab-Columbia University team believes their new approach to a single-molecule diode provides a general route for tuning nonlinear nanoscale-device phenomena that could be applied to systems beyond single-molecule junctions
and two-terminal devices.""We expect the understanding gained from this work to be applicable to ionic liquid gating in other contexts,
The paper is titled"Single-molecule diodes with high rectification ratios through environmental control.""Other co-authors are Brian Capozzi, Jianlong Xia, Olgun Adak, Emma Dell, Zhen-Fei Liu and Jeffrey Taylor r
#Sol-gel capacitor dielectric offers record-high energy storage If the material can be scaled up from laboratory samples,
Capacitors often complement batteries in these applications because they can provide large amounts of current quickly.
Perry and colleagues in Georgia Tech's Center for Organic photonics and Electronics (COPE) had been working on other capacitor materials to meet these demands
so the group decided to pursue these materials for the new capacitor applications. Using an aluminized mylar film coated with the hybrid sol-gel capacitor material,
they showed that the capacitor could be rolled and rerolled several times while maintaining high energy density, demonstrating its flexibility.
But they were still seeing high current leakage. To address that, they deposited a nanoscale self-assembled monolayer of n-octylphosphonic acid on top of the hybrid sol-gel.
though it doesn't match the lithium ion battery formats commonly used in electronic devices and vehicles.""This is the first time I've seen a capacitor beat a battery on energy density,
"said Perry.""The combination of high energy density and high power density is uncommon in the capacitor world."
"Researchers in Perry's lab have been making arrays of small sol-gel capacitors in the lab to gather information about the material's performance.
The devices are made on small substrates about an inch square.""What we see when we apply an electric field is that the polarization response
"This is what you want to see in a capacitor dielectric material.""The next step will be to scale up the materials to see if the attractive properties transfer to larger devices.
"This work emphasizes the importance of controlling the electrode-dielectric interface to maximize the performance of dielectric materials for energy storage application
By shrinking them down in size, researchers will be able to cram millions of these devices on a single chip.
In a paper published in Scientific Reports("Single-cell Migration Chip for Chemotaxis-based Microfluidic Selection of Heterogeneous Cell Populations),
#Scientists print low cost radio frequency antenna with graphene ink (Nanowerk News) Scientists have moved graphene--the incredibly strong and conductive single-atom-thick sheet of carbon--a significant step along the path
Researchers from the University of Manchester, together with BGT Materials Limited, a graphene manufacturer in the United kingdom, have printed a radio frequency antenna using compressed graphene ink.
The antenna performed well enough to make it practical for use in radio-frequency identification (RFID) tags and wireless sensors,
the antenna is flexible, environmentally friendly and could be cheaply mass-produced. The researchers present their results in the journal Applied Physics Letters,
said Zhirun Hu, a researcher in the School of Electrical and Electronic engineering at the University of Manchester."
which can be used to print circuits and other electronic components. Graphene ink is generally low cost and mechanically flexible
Paving the Way to Antennas, Wireless Sensors, and More The researchers tested their compressed graphene laminate by printing a graphene antenna onto a piece of paper.
The antenna measured approximately 14 centimeters long, and 3. 5 millimeter across and radiated radio frequency power effectively,
said Xianjun Huang, who is the first author of the paper and a Phd candidate in the Microwave and Communcations Group in the School of Electrical and Electronic engineering.
Printing electronics onto cheap, flexible materials like paper and plastic could mean that wireless technology,
like RFID tags that currently transmit identifying info on everything from cattle to car parts,
as well as sensors and wearable electronics s
#Printing 3-D graphene structures for tissue engineering Ever since single-layer graphene burst onto the science scene in 2004,
and ultra-strong and lightweight structure, graphene has potential for many applications in electronics, energy, the environment,
An expert in biomaterials, Shah said 3-D printed graphene scaffolds could play a role in tissue engineering and regenerative medicine as well as in electronic devices.
so it could be used for biodegradable sensors and medical implants. Shah said the biocompatible elastomer
Many researchers see improved interconnection of optical and electronic components as a path to more efficient computation and imaging systems.
about 20 nanometers in size the same size range as the smallest features that can now be produced in microchips.
This could lead to chips that combine optical and electronic components in a single device, with far lower losses than when such devices are made separately and then interconnected,
The work is retty criticalfor providing the understanding needed to develop optoelectronic or photonic devices based on graphene and hbn,
#Toward'green'paper-thin, flexible electronics (Nanowerk News) The rapid evolution of gadgets has brought us an impressive array of smart products from phones to tablets,
A Transparent and Photoluminescent Foldable Nanocellulose/Quantum dot Paper")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.
roll up electronics. American Chemical Society) Technology experts have predicted long the coming age of flexible electronics,
and researchers have been working on multiple fronts to reach that goal. But many of the advances rely on petroleum-based plastics and toxic materials.
wearable sensors that can do the same thing. Their technology, reported in the journal ACS Nano("Stretchable, Transparent, Ultrasensitive,
and Patchable Strain Sensor for Humanmachine Interfaces Comprising a Nanohybrid of Carbon nanotubes and Conductive Elastomers"),could help robot developers make their machines more human.
Most current efforts toward this goal analyze a person's feelings using visual sensors that can tell a smile from a frown, for example.
low-cost sensors to detect facial movements, including slight changes in gaze. The researchers created a stretchable and transparent sensor by layering a carbon nanotube film on two different kinds of electrically conductive elastomers.
They found it could tell whether subjects were laughing or crying and where they were looking.
the sensors could be used to monitor heartbeats, breathing, dysphagia (difficulty swallowing) and other health-related cues s
and well-controlled fabrication of nanotubular electrodes to accommodate ion motion in and out and close contact between the thin nested tubes to ensure fast transport for both ions and electrons.
using atomic layer deposition to carefully control thickness and length of multilayer concentric nanotubes as electrodes at each end.
what happens at the surface of a double-layer capacitor. Science Impact These nanobatteries delivered their stored energy efficiently at high power (fast charge
they can be used to create a new generation of sensors and actuators with vanishingly small heat signatures,
the researchers pass a suspension of B cells and target antigen through tiny, parallel channels etched on a chip.
society's thirst for powerful sensors is growing. Given that, few sensing techniques can match the buzz created by surface-enhanced Raman spectroscopy (SERS.
and semiconductors, are known to be important to this process and others such as photosynthesis and optical communications.
This discovery sheds light on the primary excitonic response of solids which could allow quantum control of electrons in metals, semiconductors,
"Self-assembled three-dimensional and compressible interdigitated thin-film supercapacitors and batteries")."This is a closeup of the soft battery,
enabling us to fit more electronics in a smaller space.""A 3d structure enables storage of significantly more power in less space than is possible with conventional batteries,
"Three-dimensional, porous materials have been regarded as an obstacle to building electrodes. But we have proven that this is not a problem.
While flexible and stretchable electronics already exist, the insensitivity to shock and impact are somewhat new."
and his work on aerogels is in the basis for the invention of soft electronics. Another partner is leading battery researcher, Professor Yi Cui from Stanford university y
and logic gates"),is the first step in the use of programmable cells for medical diagnosis. Bacteria have a bad reputation,
Jérôme Bonnet's team in Montpellier's Centre for Structural Biochemistry (CBS) had the idea of using concepts from synthetic biology derived from electronics to construct genetic systems making it possible to"programme"living cells like a computer.
the cornerstone of genetic programming The transistor is the central component of modern electronic systems. It acts both as a switch and as a signal amplifier.
In informatics, by combining several transistors, it is possible to construct"logic gates, "i e. systems that respond to different signal combinations according to a predetermined logic.
For example, a dual input"AND"logic gate will produce a signal only if two input signals are present.
All calculations completed by the electronic instruments we use every day, such as smartphones, rely on the use of transistors and logic gates.
During his postdoctoral fellowship at Stanford university in the United states Jérôme Bonnet invented a genetic transistor, the transcriptor.
The insertion of one or more transcriptors into bacteria transforms them into microscopic calculators. The electrical signals used in electronics are replaced by molecular signals that control gene expression.
It is thus now possible to implant simple genetic"programmes"into living cells in response to different combinations of molecules.
In this new work, the teams led by Jérôme Bonnet (CBS, Inserm U1054, CNRS UMR5048, Montpellier University), Franck Molina (Sysdiag, CNRS FRE 3690),
As a proof of concept, the authors connected the genetic transistor to a bacterial system that responds to glucose,
Low-cost pollution detectors to tackle air quality (w/video) Rush hour can be maddening. Roads congested with traffic,
With this in mind, Jonesteam, together with industrial partners and other universities, has been developing low-cost pollution detectors that are small enough to fit in your pocket,
stable enough to be installed as long-term static detectors around a city, and sensitive enough to detect small changes in air quality on a street-by-street basis. Their findings are now informing research projects aimed at improving air quality in major cities across Europe and North america.
The detectors are based on electrochemical sensors developed by project partner Alphasense for industrial safety where detection of toxic gases is needed at the parts-per-million level.
I had the confidence to believe that we could push our sensors to lower concentration levels,
and yet keep sensor costs low, says Dr John Saffell, Technical Director at Alphasense. The electrochemical devices the team developed can measure a wide range of pollutants,
They also discovered that sensor performance can create new opportunities. Jones and colleagues had to develop new smart software methods capable of separating local pollution events from background signals (pollution transported from long range)
and then to calibrate sensors across networks. Plus, they needed to move from being able to process the data after it has been collected to doing so in real-time.
For instance, sensors can be used to ask whether pollution along bus routes is improved by upgrading the exhaust processing on a bus fleet;
AQMESH uses Alphasense sensors to sample every 10 seconds, and data processing is carried out in real-time using cloud computing software similar to that developed by the Cambridge team. hen the project started in 2006 there were lone voices calling for a different approach to air quality monitoring,
and Alphasense helped us to understand the sensor full potential, and now we have a product that can be placed exactly where it needed
aims to deploy large numbers of air quality sensors across the whole of Greater london. Alphasense is providing the sensors and supporting the engineering;
and Cambridge is helping with data interpretation in a project whose ethos is ou can manage
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