#A universal transition Understanding what causes materials to change from electrical insulators to metallic conductors is relevant not only to the development of practical electronic devices,
which half of the electronic states that can contribute to the material electrical conductivity are occupied by electrons,
Therefore, rather than relying solely on electrical conductivity measurements, the researchers combined these observations with thermoelectric power measurements,
#Next-generation illumination using silicon quantum dot-based white-blue LED (Nanowerk News) A silicon quantum dot (QD)- based hybrid inorganic/organic light-emitting diode (LED) that exhibits white-blue electroluminescence
and their collaborators (Applied Physics Letters,"White-blue electroluminescence from a Si quantum dot hybrid light-emitting diode").
the laser arc method generates an arc between an anode and a cathode (the carbon) in a vacuum.
which create a strong electric field intensity gradient, are key to inducing cantilever oscillations. Because the changes of the electromagnetic field in such systems are measured in tens of nanometers,
KAIST) Another way to achieve ultralow-powered PRAM is to utilize self-structured conductive filaments (CF) instead of the resistor-type conventional heater.
"Re-grown hematite proved to be a better power generating anode, producing a record low turn-on voltage that enabled the researchers to be the first to use earth-abundant hematite
an MIT graduate student in electrical engineering and computer science and first author on the new paper. e need to regulate the input to extract the maximum power,
the Joseph F. and Nancy P. Keithley Professor in Electrical engineering, use an inductor, which is a wire wound into a coil.
so the catalyst has very good electrical conductivity and stability.''Wang used electrochemical tuning--putting lithium in, taking lithium out to test the catalytic potential of several metal oxides.'
At its most basic level, a battery is made of two metal electrodes (an anode and a cathode) with some sort of solution between them (electrolyte.
electrolyte ions are stored in the anode. As the battery discharges, electrolyte ions leave the anode
and move across the battery to chemically react with the cathode. The electrons necessary for this reaction travel through the external circuit,
generating an electric current. A supercapacitor is similar to a battery in that it can generate and store electric current,
but unlike a battery, the storage and release of energy does not involve chemical reactions: instead, positive and negative electrolyte ions simply tickto the surfaces of the electrodes when the supercapacitor is being charged.
When a supercapacitor is being discharged to power a device, the ions can easily opoff the surface
Our approach is to trap the probe light used for imaging inside of an optical resonator,
Because of the resonator, the signal gets enhanced by a factor of 50000. In the microscope, built by Dr. David Hunger and his team,
one side of the resonator is made of a plane mirror that serves at the same time as a carrier for the nanoparticles under investigation.
Laser light is coupled into the resonator through this fibre. The plane mirror is moved point by point with respect to the fibre
we can create electric fields that attract and move around droplets containing any chemical solution, "says first author Alphonsus Ng who recently graduated with a Phd from the U of T Institute of Biomaterials and Biomedical engineering (IBBME) and Donnelly Centre,
"advances the understanding and use of complex oxide materials that boast unusual properties such as superconductivity and colossal magnetoresistance but are notoriously difficult to control.
An electric current delivered by the device removes the membrane, releasing a single dose. The device can be programmed wirelessly to release individual doses for up to 16 years to treat
and Professor Chongwu Zhou of the Ming Hsieh Department of Electrical engineering, in concert with their collaborators, is documented in a paper in Advanced Materials("Black Arsenic-Phosphorus:
and manufacture of superconductors or high-efficiency solar cells and light sensors, said leader of the research,
and possibly superconductivity if properly doped.""From left are: Professor Jim Williams, Professor Andrei Rode and Associate professor Jodie Bradbury with the complex electron diffraction patterns.
the friction between those two surfaces ultimately produces an electrical charge-a type of contact electrification known as the triboelectric effect.
the characteristic that controls how polarized atoms interact with external electric fields. The researchers who published their results this month in the American Chemical Society Journal of Physical chemistry Letters discovered they could calculate the flexoelectric effect of graphene rolled into a cone of any size and length.
Lithium-ion cells with cobalt cathodes hold twice the energy of a nickel-based battery and four times that of lead acid.
These types of batteries, in all of their different lithium-anode combinations, continue to be an essential part of modern consumer electronics
which can literally sense different physical quantities such as electric field, temperature or vibrations through the inside of this hollow-core photonic crystal fibre.
which flies through the hollow channel in the interior of a photonic crystal fibre to measure different physical quantities, for example the electric field along the optical fibre.
whether hollow-core photonic crystal fibres are suitable as sensors by initially using the fibres to measure electric fields, vibrations and temperatures.
Less light passes through the fibre in a strong electric field To measure the strength of an electric field,
In an electric field it is deflected therefore from the centre of the channel to its edge,
The loss here is proportional to the strength of the electric field, and it is thus possible to determine the field from a distance.
Electric fields and vibrations can be distinguished by the behaviour of beads carrying different levels of charge.
Electric fields vibrations and temperatures, and thus three quantities that are relevant in these installations, could be recorded with a single measuring instrument t
Forschungszentrum Jlich)" Our method is the first to image electric fields near the surface of a sample quantitatively with atomic precision on the subnanometre scale,
Such electric fields surround all nanostructures like an aura. Their properties provide information, for instance, on the distribution of charges in atoms or molecules.
To image electric fields up until now, scientists have used the entire front part of the scanning tip as a Kelvin probe.
but rather two electric fields that act on the mobile electron of the molecular sensor: the first is the field of a nanostructure being measured,
we can create a very sharp image of the electric field of the sample. Its a bit like a camera with very small pixels."
"In a new study, electrical engineers at the University of California, San diego have designed a cloaking device that is both thin
"said Li-Yi Hsu, electrical engineering Ph d. student at UC San diego and the first author of the study,
which was published recently in the journal Progress In Electromagnetics Research("Extremely Thin Dielectric Metasurface for Carpet Cloaking").
"An extremely thin cloaking device is designed using dielectric materials. The cloak is a thin Teflon sheet (light blue) embedded with many small, cylindrical ceramic particles (dark blue.
The researchers report that one of the keys to their cloak's design is the use of nonconductive materials called dielectrics,
This cloak includes two dielectrics, a proprietary ceramic and Teflon, which are tailored structurally on a very fine scale to change the way light waves reflect off of the cloak.
In addition, Yu envisions simply letting the resonator emit that energy in the form of infrared light toward the sky,
These are at the root of some of quantum physics'most fascinating phenomena, such as superfluidity and superconductivity.
and an interconnection material linking semiconductor devices to form the desired electrical circuits, "said Kim.""This renders high processing temperature undesirable,
ISEM is the program leader for electrification and plays crucial role for design of next generation electric vehicles A key to unlocking the electric vehicle capability is a lightweight and powerful battery pack. ur simple fabrication method of eco-friendly materials
Doping the zinc oxide causes it to behave like a metal at certain wavelengths and like a dielectric at other wavelengths.
the addition of boron and nitrogen to graphenes carbon to connote the conductivity necessary to produce an electrical insulator.
reportedly harvests the electromagnetic radiation transferring to and from mobile phones and converts it into direct current (DC) electrical energy,
Selective biosensors transduce chemical signals into an electric current, which regulates electrophoretic delivery of chemical substances without necessitating liquid flow.
The energy of the radio waves the router sent out was converted into direct current voltage with a component called a rectifier,
The electrical engineers used their frequency comb to synchronize the frequency variations of the different streams of optical information,
first author on the paper and a UCSD electrical engineering Phd student. he frequency comb ensured that the system did not accumulate the random distortions that make it impossible to reassemble the original content at the receiver. he laboratory experiments involved setups with both three and five optical channels,
an associate professor in the campus electrical engineering and computer sciences department, developed the new algorithm. Abbeel said the best thing about the technique is that it rids the need of reprogramming
they were able to create a 3d electrical circuit. Found in the cell walls of plants and algae or secreted by bacteria,
Two different metals, a anode and a cathode are submerged into different solutions and are connected by a salt bridge to form a reaction,
including resistors, switches, transistors, and, indeed, diodes. They have learned that it is possible to see quantum mechanical effects
Liquid nitrogen cooled superconductors and permanent magnets combine to allow Lexus to create the impossible. Now, Lexus, your hoverboard is really cool, but"impossible"?
Lexus is taking advantage of key properties of materials called superconductors. As you might expect,
When superconductors are cooled below a certain temperature, their electrons buddy up and move through the material without encountering any sort of resistance.
More specifically, Lexus'use of liquid nitrogenhich has a temperature of-321 degrees Fahrenheitells us that they're using a high-temperature superconductor like yttrium barium copper oxide,
Lexus'superconductor probably starts working at about-292 degrees Fahrenheit, which sounds unfathomably cold. However, this temperature is actually quite warm by superconductor standards.
The first superconductor ever discovered, in 1911, had to be cooled down to-452 degrees Fahrenheit, only a few degrees warmer than absolute zero, the coldest possible temperature.
So how did Lexus float its high-temperature superconductors? By playing a magnetic trick on them.
When a high-temperature superconductor is too warm to work, magnetic fields can pass right through it without a problem.
But if you then cool the superconductor down so that it starts working, it gets"stuck"on the magnetic field lines that were passing through it,
as if it were caught in a magnetic spiderweb. In other words, superconductors"freeze the flux lines of the field,
"says Steve Gourlay, the head of the Lawrence Berkeley National Lab's Superconducting Magnet Group, leaving the superconductor embedded in the magnetic field at that particular location.
A cross-section of a high-temperature superconductor (blue rectangle)" embedded"in a magnetic field (black lines. The magnetic channels through the superconductor are called"quantum vortices."
"How cool is that?(Wikimedia Commons) To levitate the superconductor, all you need to do is embed the superconductor in the magnetic field a couple of inches above some kind of magnetic surface.
If you tried to move the superconductor, you'd kickstart circular eddies of electrical current on the superconductor's surface,
spawning miniature magnetic fields that work to the superconductor in place. These eddy currents even oppose gravity,
pushing off of the surface's magnetic field to keep the superconductor floating in midair. In normal conducting material such as copper,
which resists the flow of electricity, those eddies would weaken. The lack of electrical resistance in superconductors means that once an eddy current starts
nothing can sap its strength. As long as you keep the superconductor cold, it'll stay floating above a magnet,
its eddy currents fighting gravity to a Draw in short, Lexus has come up with a cool way to use superconductors to levitate a hoverboard and its rider, an impressive achievement,
if true--Lexus hasn't provided video of someone riding the board. But by now, you've probably noticed a theme:
levitation happens when the superconductor interacts with an outside magnetic field. And this is where Lexus is giving us a little movie magic.
If the superconductors are in the hoverboard, then we need an outside magnetic field for the hoverboard to coast on.
This is where Lexus'"permanent magnets"come in. Gourlay suspects that Lexus laid down a bunch of very strong rare-earth magnets underneath the"sidewalk,
"setting up a magnetic field powerful enough to support both board and, Lexus promises, a rider.
In fact, Gizmodo reports that the hoverboard only works on"special metallic surfaces.""This sort of setup is probably too expensive for your everyday skate park.
so in the future you might not have to hunt around for your charging adapter every evening.
fabricated and tested by a team of Penn State electrical engineers that can provide exceptional capabilities for manipulating light.
which consists of a periodic array of strongly coupled nanorod resonators, could improve systems that perform optical characterization in scientific devices, such as ellipsometers;
a postdoctoral fellow in electrical engineering and lead author of a recent paper in Scientific Reports explaining their invention."
Co-authors include Seokho Yun, a former postdoctoral scholar in the Penn State Electrical engineering Department, Douglas H. Werner, John L. and Genevieve H. Mccain Chair Professor of Electrical engineering
, Zhiwen Liu, associate professor of electrical engineering, and Theresa Mayer, Distinguished Professor of Electrical engineering. The paper is titled"Broadband and Wide field-of-view Plasmonic Metasurface-enabled Waveplates."
"This work was supported by the National Science Foundation through Penn State's Center for Nanoscale Science e
But existing electroporation methods require high electric field strengths and for cells to be suspended in solution,
Researchers are using the glass as a cathode material as recently reported in Scientific Reports a journal from the publishers of Nature.
In crystalline form vanadium pentoxide can take three positively charged lithium ions--three times more than materials presently used in cathodes such as lithium iron phosphate.
To produce the cathode material Afyon and his colleagues blended powdered vanadium pentoxide with borate compounds.
Afyon used this vanadate-borate glass powder for the battery cathodes which he then placed in prototypes for coin cell batteries to undergo numerous charge/discharge cycles.
Thus we have invented a way to make a perfect transition between the nanowire and a superconductor.
The superconductor in this case is aluminium. There is great potential in this, "says Associate professor Thomas Sand Jespersen,
or something blocking the object that causes a systematic error in the detector says Lawson Wong a graduate student in electrical engineering
and then bring them together explains Faraz Najafi a graduate student in electrical engineering and computer science at MIT and first author on the new paper.
or hundreds of photonic qubits it becomes unwieldy to do this using traditional optical components says Dirk Englund the Jamieson Career development Assistant professor in Electrical engineering and Computer science at MIT and corresponding author on the new paper.
which is led by Karl Berggren an associate professor of electrical engineering and computer science and of which Najafi is a member.
which they deposit the superconductor niobium nitride in a pattern useful for photon detection. At both ends of the resulting detector they deposit gold electrodes.
"Potential applications range from battery anodes, to solar cells, to 3d electronic circuits and biomedical devices.""The 3d transformation process involves a balance between the forces of adhesion to the substrate and the strain energies of the bent,
including semiconductors, conductors and dielectrics.""""This work establishes the concepts and a framework of understanding.
while still ensuring optimal electrical conductivity. Finally, a fluidic microchannel enables the delivery of pharmacological substances--neurotransmitters in this case--that will reanimate the nerve cells beneath the injured tissue.
when the electric arc is burning causing the pressure in the oil and gas to rise dramatically.
With better knowledge and new mathematical models we will be able to observe the relationships between the physics of electric arcs the transformer tank and the electrical protection system.
As you're reading the front of the queue the whole front of the queue will be in your cache says Justin Kopinsky an MIT graduate student in electrical engineering
Moreover their method enables this value to be tuned through the application of an electric field meaning graphene circuit elements made in this way could one day be rewired dynamically without physically altering the device.
Applying an electric field pulse can change the sign of the surface charges. That's an unstable situation Rappe said in that the positively charged surface will want to accumulate negative charges and vice versa.
You could come along with a tip that produces a certain electric field and just by putting it near the oxide you could change its polarity Martin said.
or dielectrics opening up the possibility of water repellent electronics. Funding was provided by the Bill & Melinda Gates Foundation and the United states Air force Office of Scientific research h
#High-temperature superconductivity in atomically thin films A research group has succeeded in fabricating an atomically thin,
high-temperature superconductor film with a superconducting transition temperature (Tc) of up to 60 K(-213°C). The team also established the method to control/tune the Tc.
This finding not only provides an ideal platform for investigating the mechanism of superconductivity in the two-dimensional system,
because the unique quantum effects in superconductors are a great advantage in achieving the energy saving
the device application of superconductors has long been hindered. The largest obstacle is the necessity of a huge and expensive cooling system with liquid helium, because of the low Tc of conventional superconductors,
which is close to absolute zero (0 K, --273°C)* 1. It has also been a big challenge to realize the high-density integration of superconductors into electronic devices.
In order to overcome these problems, it is definitely necessary to develop a new superconductor with higher-Tc,
that can be fabricated into a thin film. The research team at Tohoku University turned its attention to iron selenide (Fese
which is a member of iron-based superconductors*2 . While the Tc of bulk Fese is only 8 K(-265°C a signature of higher-Tc superconductivity has been suggested in ultrathin film
and its verification has been required urgently. The researchers at first fabricated high-quality, atomically thin Fese films Fig. 1, with thickness of between one monolayer (which corresponds to three-atoms thickness) and twenty monolayers (sixty-atoms thickness),
which is direct evidence of the emergence of superconductivity in the films. The researchers found that the Tc estimated from the gap-closing in a monolayer film is surprisingly high (above 60 K),
While multilayer films do not show superconductivity in the as-grown state, the researchers have discovered a novel method to deposit alkali atoms onto the films
the researchers have succeeded in converting non-superconducting multilayer Fese films into high-Tc superconductors with Tc as high as 50 K. The present result gives a great impact to both the basic
and applied researches in superconductors. The researchers have shown clearly how the superconductivity is emerged, enhanced and controlled in atomically thin Fese films.
While the Tc achieved in this study (50-60 K) is still lower than that of the cuprate high-Tc superconductors (highest Tc?
135 K) which caused the"high-Tc fever"in the world 30 years ago, it obviously exceeds the record of other"high-Tc superconductors"such as fullerene (C60) superconductors (Tc 33 K) and Mgb2 (Tc 39k),
closely approaching the temperature of liquid nitrogen (77 K). The present report would lead to intensive researches to further increase Tc by changing the number of atomic layers, the amount of doped electrons and the species of substrate.
and applied researches on superconductivity, because the Tc of 50-60 K achieved in the present study is high enough to keep the superconducting state by using a closed-cycle-gas-type cooling system without liquid helium.
The present success in fabricating an atomically thin high-temperature superconductor not only provides an ideal platform to investigate the novel two-dimensional superconductivity,
The ultrathin high-Tc superconductor would effectively contribute to the significant downsizing and consequent high-density integration in electric circuits,
uses an inexpensive air-breathing cathode created with nickel sprayed onto one side of ordinary office paper.
The anode is screen printed with carbon paints creating a hydrophilic zone with wax boundaries.
Seunghyup Yoo (Electrical engineering) have succeeded in developing LEDS based on graphene quantum dots. Highly pure GQDS were synthesized by an environmentally-friendly method designed by Prof.
"says Datta, a coauthor on the paper and Penn State professor of electrical engineering.""Resonant tunneling diodes with NDR can be used to build high frequency oscillators.
said Zhifeng Ren, principal investigator at the Texas Center for Superconductivity at UH (Tcsuh.""This is a form for the quick screening of materials,
so the catalyst has very good electrical conductivity and stability.''Wang used electrochemical tuning--putting lithium in, taking lithium out to test the catalytic potential of several metal oxides.'
temperature, chemicals, electric field or magnetic field. These various stimuli can be used to make the materials change colour,
we can create electric fields that attract and move around droplets containing any chemical solution, "says first author Alphonsus Ng who recently graduated with a Phd from the U of T Institute of Biomaterials and Biomedical engineering (IBBME) and Donnelly Centre,
"Our approach is to trap the probe light used for imaging inside of an optical resonator,
Because of the resonator, the signal gets enhanced by a factor of 50000.""In the microscope, built by Dr. David Hunger and his team,
one side of the resonator is made of a plane mirror that serves at the same time as a carrier for the nanoparticles under investigation.
Laser light is coupled into the resonator through this fibre. The plane mirror is moved point by point with respect to the fibre
and a CMOS wafer that contains the signal processing circuitry, "explained Horsley.""These wafers are bonded together,
#New method of quantum entanglement packs vastly more data in a photon A team of researchers led by UCLA electrical engineers has demonstrated a new way to harness light particles,
a UCLA associate professor of electrical engineering who was the research project's principal investigator. Researchers from MIT
The idea was to take a Cooper pair--a pair of electrons that allows electricity to flow freely in superconductors
while tunneling--a quantum phenomenon--across a junction between two superconductor leads, to pass through two separate"quantum dots"--small crystals that have quantum properties."
Signal processing in the intracellular domain of the precursor-protein-producing cells is responsible for modifications that likely induce a relative positional change of the dimerization partners and
the intracellular signal processing for single precursor proteins may be inhibited in order to specifically knock out the growth factors required by individual cancer types s
In addition, Yu envisions simply letting the resonator emit that energy in the form of infrared light toward the sky,
They also allow for handy things like electrical conductivity in metals. Atomic moments in local-moment ferromagnets--that is, common magnetic materials--align all of their spins in the same direction.
Quality map calculated Measurements of the electrical conductivity showed that the newly developed composite electrode is comparable to a conventional silver grid electrode.
and predict the electrical conductivity of the electrodes from them.""We are investigating where a given continuous conductive path of nanowires is interrupted to see where the network is not yet optimum,
whether it contained actual data or the aforementioned power traffic into direct current voltage, which was boosted then to a usable voltage with a DC-DC converter.
as well as studying how to expand this technique to other materials such as semiconductors or dielectrics, opening up the possibility of water repellent electronics.
Sunlight to electricity Solar cells work by converting photons of sunlight into an electric current that moves between two electrodes.
The device is based on microfluidic technology developed by Joel Voldman an MIT professor of electrical engineering and computer science (EECS) in 2009.
Purdue University researchers had created previously uperlatticesfrom layers of the metal titanium nitride and the dielectric, or insulator, aluminum scandium nitride.
Their discovery that nanosheets of manganese dioxide can maintain a rechargable sulphur cathode helps to overcome a primary hurdle to building a Li-S battery.
sulphur can provide a competitive cathode material to lithium cobalt oxide in current lithium-ion cells.
Unfortunately, the sulphur cathode exhausts itself after only a few cycles because the sulphur dissolves into the electrolyte solution as it reduced by incoming electrons to form polysulphides.
The result is a high-performance cathode that can recharge more than 2000 cycles. Postdoctoral research associate Xiao Liang, the lead author,
The IMS researchers around electrical engineer Dr. Gerd vom Bögel and physicist Dr. Andreas Goehlich have mastered just these two challenges:
The design consists of an ultra-thin metal anode made of thin lithium on copper
Solid Polymer Ionic Liquid (SPIL) electrolyte enables the ultra-thin lithium metal anode and improves the cell-level energy density by 50%compared to graphite anodes
and 30%compared to silicon-composite anodes. Batteries are safe nonflammable and nonvolatile and can operate at elevated temperatures.
It can be manufactured using existing Li-ion manufacturing facility leveraging mature infrastructure. The company says its prototype can be recharged 300 times while retaining 80%of its original storage capacityloser to
said Noel C. Giebink, assistant professor of electrical engineering, Penn State. urrent CPV systems are the size of billboards
and Edward Chen, who is also a graduate student studying under the guidance of Englund at MIT. oupling the NV centers with these optical resonator cavities seemed to preserve the NV spin coherence timehe duration of the memory,
a liquid cathode and a solid lithium anode, exhibited encouraging early results, encompassing many of the features desired in a state-of-the-art energy storage device.
Before the new battery hits the shelves, researchers still have a lot of work ahead of them considering the lithium anode
such as zinc and magnesium that could serve as the anode in a battery of this type. e also expect that other organometallic compounds with multi-valence-state metal centers (redox centers) may also function as the anode,
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