#Graphene displays clear prospects for flexible electronics Published in the scientific journal Nature Materials, University of Manchester and University of Sheffield researchers show that new 2d esigner materialscan be produced to create flexible, see-through and more efficient electronic devices.
Being so thin, at only 10-40 atoms thick, these new components can form the basis for the first generation of semitransparent smart devices.
One-atom thick graphene was isolated first and explored in 2004 at The University of Manchester.
and introducing quantum wells to control the movement of electrons, new possibilities for graphene based optoelectronics have now been realised.
the quantum efficiency (photons emitted per electron injected) is already comparable to organic LEDS. Source: University of Mancheste
The nonlinear interaction between the light and the gas atoms in the special fibre makes different wavelengths travel at different velocities.
They can rip electrons away from their atoms they can accelerate electrons they can help to monitor the dynamics of chemical reactions.
they focused the pulse onto a target of xenon gas ionizing the xenon atoms. Depending on the exact shape of the laser pulse the electrons ripped away from the xenon atoms can be sent into different directions. t is an ultrafast electron switchsays Tadas Balciunas.
The photonics team at the Vienna University of Technology is planning to use this new technology for a variety of measurements in the future
#Nanoscale mirrored cavities amplify connect quantum memories The idea of computing systems based on controlling atomic spins just got a boost from new research performed at the Massachusetts institute of technology (MIT) and the U s. Department of energy (DOE) Brookhaven National Laboratory.
By constructing tiny irrorsto trap light around impurity atoms in diamond crystals, the team dramatically increased the efficiency with
which photons transmit information about those atomselectronic spin states, which can be used to store quantum information.
Such spin-photon interfaces are thought to be essential for connecting distant quantum memories, which could open the door to quantum computers and long-distance cryptographic systems.
Photons that enter these nanoscale funhouses bounce back and forth up to 10 000 times, greatly enhancing their chance of interacting with the electrons in the NV center.
Crucially, the team demonstrated a spin-coherence time (how long the memory encoded in the electron spin state lasts) of more than 200 microseconds long time in the context of the rate at
which computational operations take place. A long coherence time is essential for quantum computing systems and long-range cryptographic networks. ur research demonstrates a technique to extend the storage time of quantum memories in solids that are coupled efficiently to photons,
which is essential to scaling up such quantum memories for functional quantum computing systems and networks, said MIT Dirk Englund,
and characterize the materials. he memory elements described in this research are the spin states of electrons in nitrogen-vacancy (NV) centers in diamond.
The NV consists of a nitrogen atom in the place of a carbon atom, adjacent to a crystal vacancy inside the carbon lattice of diamond.
The up or down orientation of the electron spins on these NV centers can be used to encode information in a way that is somewhat analogous to how the charge of many electrons is used to encode the and in a classical computer.
The scientists preferentially orient the NV spin, whose direction is oriented naturally randomly, along a particular direction.
scientists can manipulate the electron spins into or back into using microwaves. The state has brighter fluorescence than the state,
The trick is getting the electron spins in the NV centers to hold onto the stable spin states long enough to perform these logic gate operationsnd being able to transfer information among the individual memory elements to create actual computing networks
. t is already possible to transfer information about the electron spin state via photons but we have to make the interface between the photons and electrons more efficient.
The trouble is that photons and electrons normally interact only very weakly. To increase the interaction between photons and the NV,
we build an optical cavity trap for photonsround the NV, Englund said. These cavities, nanofabricated at Brookhaven by MIT graduate student Luozhou Li with the help of staff scientist Ming Lu of the CFN, consist of layers of diamond
and air tightly spaced around the impurity atom of an NV center. At each interface between the layers there a little bit of reflectionike the reflections from a glass surface.
With each layer the reflections add upike the reflections in a funhouse filled with mirrors.
Photons that enter these nanoscale funhouses bounce back and forth up to 10,000 times, greatly enhancing their chance of interacting with the electrons in the NV center.
This increases the efficiency of information transfer between photons and the NV center electron spin state.
The devicesperformance was characterized in part using optical microscopy in a magnetic field at the CFN, performed by CFN staff scientist Mircea Cotlet, Luozhou Li,
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,
Cotlet said. Added Englund: hese methods have given us a great starting point for translating information between the spin states of the electrons among multiple NV centers.
These results are an important part of validating the scientific promise of NV-cavity systems for quantum networking.
he transferred hard mask lithography technique that we have developed in this work would benefit most unconventional substrates that aren suitable for typical high-resolution patterning by electron beam lithography.
and shuttle data with light instead of electrons. Electrical and computer engineering associate professor Rajesh Menon and colleagues describe their invention today in the journal Nature Photonics.
or shuttled is done through light instead of electrons. Image credit: Dan Hixson/University of Utah College of Engineeringsilicon photonics could significantly increase the power and speed of machines such as supercomputers, data center servers and the specialized computers that direct autonomous cars and drones with collision detection.
says Menon. ut that information has to be converted to electrons when it comes into your laptop.
Photons of light carry information over the Internet through fiber-optic networks. But once a data stream reaches a home or office destination
the photons of light must be converted to electrons before a router or computer can handle the information.
And because photonic chips shuttle photons instead of electrons mobile devices such as smartphones or tablets built with this technology would consume less power,
The new findings using a layer of one-atom-thick graphene deposited on top of a similar 2-D layer of a material called hexagonal boron nitride (hbn) are published in the journal Nano Letters.
Although the two materials are structurally similar both composed of hexagonal arrays of atoms that form two-dimensional sheets they each interact with light quite differently.
Light interaction with graphene produces particles called plasmons while light interacting with hbn produces phonons.
he says. t could even enable single-molecule resolution, Fang says, of biomolecules placed on the hybrid material surface.
which molecules pump other molecules. This tiny machine is no small feat. The pump one day might be used to power other molecular machines,
The new machine mimics the pumping mechanism of life-sustaining proteins that move small molecules around living cells to metabolize and store energy from food.
For its food, the artificial pump draws power from chemical reactions, driving molecules step-by-step from a low energy state to a high-energy state far away from equilibrium.
Youtube video screenshotur molecular pump is radical chemistry an ingenious way of transferring energy from molecule to molecule,
and redistribute molecules around their cells, using vital carrier proteins, he said. e are trying to recreate the actions of these proteins using relatively simple small molecules we make in the laboratory. huyang Cheng, a fourth-year graduate student in Stoddart laboratory and first author of the paper,
has spent his Ph d. studies researching molecules that mimic nature biochemical machinery. He first designed an artificial pump two years ago,
but it required more than a year of testing prototypes before he found the ideal chemical structure. n some respects,
we are asking the molecules to behave in a way that they would not do said normally, Cheng. t is much like trying to push two magnets together.
The ring-shaped molecules we work with repel one another under normal circumstances. The artificial pump is able to syphon off some of the energy that changes hands during a chemical reaction
that allows molecules to flow phillenergetically. his is non-equilibrium chemistry, moving molecules far away from their minimum energy state,
with simple artificial molecules, is one of the major challenges for science in the 21st century. ltimately,
The researchers have identified a molecule called MCAM, and they have shown that blocking this molecule could delay the onset of the disease
and significantly slow its progression. These encouraging results from in vitro tests in humans and in vivo tests in mice were published in the Annals of Neurology. e believe we have identified the first therapy that will impact the quality of life of people with multiple sclerosis by significantly reducing the disability and the disease progression
#Semiliquid Battery Almost As good as its Lithium Ion Counterparts and Supercapacitators Developed by researchers at the University of Texas, Austin,
A new semiliquid battery combines all that is best about its lithium ion counterparts and supercapacitators (pictured above) to bring us closer to the next generation of energy storage devices.
and reasonable energy density, representing a promising prototype liquid redox battery with both high energy density and power density for energy storage.
though slightly lower than that of lithium-ion batteries. This combination is a real winner considering that the battery is designed mostly for use in hybrid electric vehicles and energy storage for renewable energy sources.
Yu and his team attribute the battery stellar performance in large part to its liquid electrode design. he ions can move through the liquid battery very rapidly compared to in a solid battery,
and the redox reactions in which the electrons are transferred between electrodes also occur at very high rates in this particular battery.
a small molecule that attaches to our DNA and acts like a switch to turn genes on and off (an effect known as epigenetics).
where particles occupy the corners and center of a cube (left), to a more compact aughter phase (right.
making materials that can transform so we can take advantage of properties that emerge with the particlesrearrangements. he ability to direct particle rearrangements,
or a combination of these forces between particles. e know that properties of materials built from nanoparticles are strongly dependent on their arrangements,
the lead author on the paper. ltering these shells can selectively shift the particle-particle interactions,
These reprogrammed interactions impose new constraints on the particles, forcing them to achieve a new structural organization to satisfy those constraints. sing their method,
or configurations, of the same particle combinations. This is quite different from phase changes driven by external physical conditions such as pressure or temperature,
Hud and colleagues had wondered if the molecules necessary for life, such as the ancestor of DNA, could have developed in a water-free solution.
the chemistry necessary to make the molecules of life would be much easier without water being present. his work was inspired by research into the origins of life with the basic question of
how do you detect a very rare mutation in a large pile of healthy DNA molecules?
and sink (the goat) are sequence-specific DNA molecules that root out single-nucleotide variant targets in solutions that also include healthy ild-typesequences.
It has been engineered genetically to produce a molecule called GM-CSF, which stimulates the immune system to attack
#Researchers Discover Electron Pairing without Superconductivity A team of physicists from the University of Pittsburgh, the University of Wisconsin-Madison,
and the U s. Naval Research Laboratory (NRL) has discovered electron pairing in strontium titanate far above the superconducting transition temperature.
which electrons form pairs that do not condense into a superconducting phase. The complete findings are published in the May 14,
The basis for all superconductors is the formation of electron pairs. In the normal non-superconducting phase, the electrons in most metals move independentlyhe scattering of electrons causes electrical resistance.
In a superconductor, the paired electrons move in a highly coordinated fashion that has zero electrical resistance.
The new research identified an intermediate phase in which electrons form pairs, but the pairs move independently.
The independent pairs are able to scatter, and the phase exhibits electrical resistance. The researchers used quantum dots in strontium titanate to observe the electron pairs.
Quantum dots are small regions of a material in which the number of electrons can be controlled precisely,
in this case using an electrostatic gate. The quantum dots were large enough to support a superconducting phase at low temperatures
but the researchers observed that the dots always preferred an even number of electrons in the new phase at higher temperatures.
they observed breaking of the electron pairs one at a time. A theory of electron pairing without formation of a superconducting state was published first by David M. Eagles in 1969.
C. Stephen Hellberg, a physicist in NRL Material Science and Technology Division and the team theorist, observed he results are described well by a simple model with attractive interactions between electrons.
We still don know the origin of the attractive interaction: possibilities include egative-Udefect centers and bipolarons.
These images show differential conductance through the quantum dot as a function of the gate voltage that controls the number of electrons in the dot (x-axis) and the applied magnetic field (y-axis).
) Blue regions have low differential conductance and a constant number of electrons; green, yellow, and brown show higher differential conductance, indicating a change in the number of electrons in the dot.
The top panel shows the measured differential conductance; the bottom panel shows the theoretical calculation (which has no disorder.
Both experiment and theory show splitting of the electron pairs with increasing field and reentrant pairing at higher fields (the merging of pairs of boundaries into vertical boundaries) l
Previously, scientists could examine changes in nanostructures only by looking at the large-scale alterations of a bulk population of particles
This is necessary because materials are susceptible to being destroyed by the high energy electron beam that is used to image them.
and Applied science and California Nanosystems Institute has identified an unexpectedly general set of rules that determine which molecules can cause the immune system to become vulnerable to the autoimmune disorders lupus and psoriasis.
The receptor triggers the cells to send signaling molecules called interferons to initiate a powerful defensive response.
researchers determined that a broad range of molecules, both organic and inorganic, can organize self-DNA into a liquid crystalline structure that binds strongly to the TLR9 receptors like the teeth on either side of a zipper.
Synchrotron X-ray scattering utilizes a particle accelerator to generate X-ray beams that allow researchers to determine how atoms
and molecules are organized into different structures. ur research has identified a set of rules that tell us what types of molecules
ur colleagues had established empirically that certain molecules were activating self-DNA and triggering responses in disorders such as lupus and psoriasis.
We were able to elucidate something that was understood poorly a key to triggering the immune response is that the molecules must arrange the DNA
#Single Atom Building blocks For Future Electronics The material is called a silicene, a layer of silicon single atoms arranged in a honeycomb pattern that was fabricated first by researchers at UOW Institute for Superconducting and Electronic Materials (ISEM) and their partners in Europe and China.
An ISEM team led by Professor Shi Xue Dou and Dr Yi Du have published breakthrough research into a new material call silicene.
Silicene great promise is related to how electrons can streak across it at incredible speed close to the speed of light.
Propelling the electrons in silicene requires minimal energy input, which means reducing power and cooling requirements for electronic devices. f silicene could be used to build electronic devices,
Dr Du team had to reak the laws of chemistryand create an artificial environment using an ultra-high vacuum. hen we vibrate the silicon atoms it causes heat
and the atoms disassemble, Dr Du said. hen we use two small robotic arms that we move with a hand-held video game controller to catch the atoms in the vacuum chamber
and place them one at a time on a plate to form the silicene paper. he process is like laying bricks,
only these are bricks are the size of a single atom. A 1 centimetre-long chain contains 10 million silicon atoms.
Studying the fundamental physics is helping the researchers build a more complete picture of the material,
cutaway view of the geometry used to generate currents of spin from currents of heat.
This current of heat creates a separation of electron spins that then diffuse through the Cu heat sink and affect the magnetization of a second ferromagnetic layer,
Alex Jerez, Imaging Technology Group, The Beckman Institutee use the spin current created by ultrafast heat conduction to generate spin transfer torque.
Spin transfer torque is the transfer of the spin angular momentum from conduction electrons to the magnetization of a ferromagnet
and enables the manipulation of nanomagnets with spin currents rather than magnetic fields, explained Gyung-Min Choi,
hermal spin transfer torque driven by the spin-dependent Seebeck effect in metallic spin-valves,
The spin-dependent Seebeck effect refers to the analogous phenomenon involving the spin of electrons in a ferromagnet.
e quantify thermal spin transfer torque in metallic spin valve structures using an intense and ultrafast heat current created by picosecondne trillionth of a secondulses of laser light,
The sign and magnitude of the heat-driven spin current can be controlled by the composition of a ferromagnetic layer and thickness of a heat sink layer. ource:
Science museum London/Science and Society Picture Library) via Wikimediaamines are related to relatively simple molecule ammonia (NH3),
Polymer material produced by a 3-D printer includes soft, flexible material (clear or lighter tone) with particles of hard material (black) embedded, in predetermined arrangements.
its surface become bumpy in a pattern determined by the hard particles. Photo: Felice Frankelthe process, developed using detailed computer simulations,
More rigid particles are embedded within a matrix of a more flexible polymer. When squeezed, the material surface changes from smooth to a pattern determined by the spacing and shapes of the implanted harder particles;
when released, it reverts back to the original form. The findings, which the researchers say could lead to a new class of materials with dynamically controllable and reversible surface properties,
a former MIT professor of mechanical engineering who is now dean of engineering at Columbia University. epending on the arrangement of the particles,
This animated simulation shows how embedded hard particles within a softer flexible material produce a textured surface when compressed.
But by arranging the distribution of the hard particles, it can also be used to produce highly complex surface textures for example,
Using embedded particles that are elongated instead of round could also allow for the creation of surface textures that are asymmetrical.
The key to the drug potential involves a molecule the body produces that is known as prostaglandin E2, or PGE2.
and Gerson laboratories to determine the effect of SW033291 on mice that had received lethal doses of radiation
Unlike most of the commercially available detectors, RAPID can spot photons (light particles) of both visible and infrared light (wavelengths from 0. 4. 6 micrometres.
the increased spectral coverage means that far more photons can be gathered, especially from infrared wavelengths, where many objects shine most brilliantly.
Every photon arriving into the detector is converted into many more than one electron, therefore easing its detection.
Molecules of carbon and other greenhouse gases absorb heat. The more greenhouse gases emitted into the atmosphere,
a metal-binding molecule known as a ligand is applied. The type of ligand the research team designed has three branches,
which converge on the metal atoms and hold them in the aperture between their tips.
Because of neodymium slightly larger size, the tips don get as close together as they do around dysprosium atoms. he difference in size between the two ions is not that significant,
The combination of the two neodymium complexes, known as a dimer, encapsulates the neodymium ions, enabling them to dissolve in solvents like benzene or toluene.
unlike X-ray, CT SCANS or PET scans, it delivers no ionizing radiation to patients. For the past decade, research groups around the globe,
While yet other mass spectrometry-based techniques such as desorption electrospray ionization and rapid evaporative ionization mass spectrometry are being evaluated for classifying tumors and providing prognostic information,
and guides the strands to ribosomes. eif4e is thought thereby to be essential for the production of all proteins, the final effector molecules that guide every cellular event.
potentially toxic molecules that accumulate when cells are under stress, such as that caused by oncogenic transformation.
In photosynthesis, plants that are exposed to sunlight use carefully organized nanoscale structures within their cells to rapidly separate charges pulling electrons away from the positively charged molecule that is left behind,
The polymer donor absorbs sunlight and passes electrons to the fullerene acceptor; the process generates electrical energy.
because the electrons sometimes hop back to the polymer spaghetti and are lost. The UCLA technology arranges the elements more neatly like small bundles of uncooked spaghetti with precisely placed meatballs.
The fullerenes inside the structure take electrons from the polymers and toss them to the outside fullerene
which can effectively keep the electrons away from the polymer for weeks. hen the charges never come back together,
led the team that created the uniquely designed molecules. e don have these materials in a real device yet;
this one generates the particles in a few hours and uses only a handful of ingredients, including store-bought molasses.
or fluorescing molecules to help detect them in the body. Secondly these particles are coated with polymers,
which fine-tune their optical properties and their rate of degradation in the body. These polymers can be loaded with drugs that are released gradually.
However, scientists have to make sure they coated particles properly, so they used vibrational spectroscopic techniques to identify the molecular structure of the nanoparticles and their cargo.
They used spectroscopy to confirm the formulation as well as visualize the delivery of the particles and drug molecules.
Scientists also found that they can alter the infusion of the particles into melanoma cells by adjusting the polymer coatings.
as well as to make it carry several different drugs at the same time to allow for a multidrug therapy with the same particles.
The researchers connected the two to create a new molecule, with one end that was water-loving
A mixture of these molecules self-assembled into a vesicle, much like the coalescing of oil droplets in water,
The resulting lack of oxygen or ypoxiamade the hydrophobic NI molecules turn hydrophilic, causing the vesicles to rapidly fall apart
when enzymes called TET enzymes add oxygen to methylated DNA a DNA molecule with smaller molecules of methyl attached to the cytosine base.
and living mice with an amino acid called L-methionine, enriched for naturally occurring stable isotopes of carbon and hydrogen,
and measuring the uptake of these isotopes to 5fc in DNA. The lack of uptake in the non-dividing adult brain tissue pointed to the fact that 5fc can be a stable modification:
if it was a transient molecule, this uptake of isotopes would be high. The researchers believe that 5fc might alter the way DNA is recognised by proteins. nmodified DNA interacts with a specific set of proteins,
and the presence of 5fc could change these interactions either directly or indirectly by changing the shape of the DNA duplex,
said Bachman. different shape means that a DNA molecule could then attract different proteins and transcription factors,
#New manufacturing approach slices lithium-ion battery cost in half An advanced manufacturing approach for lithium-ion batteries, developed by researchers at MIT and at a spinoff company called 24m,
The existing process for manufacturing lithium-ion batteries, he says, has changed hardly in the two decades
In this so-called low battery, the electrodes are suspensions of tiny particles carried by a liquid
it is composed of a similar semisolid, colloidal suspension of particles. Chiang and Carter refer to this as a emisolid battery.
while a flow battery system is appropriate for battery chemistries with a low energy density (those that can only store a limited amount of energy for a given weight),
for high-energy density devices such as lithium-ion batteries, the extra complexity and components of a flow system would add unnecessary extra cost.
e realized that a better way to make use of this flowable electrode technology was to reinvent the lithium ion manufacturing process.
Having the electrode in the form of tiny suspended particles instead of consolidated slabs greatly reduces the path length for charged particles as they move through the material a property known as ortuosity.
While conventional lithium-ion batteries are composed of brittle electrodes that can crack under stress, the new formulation produces battery cells that can be bent,
With traditional lithium-ion production plants must be built at large scale from the beginning in order to keep down unit costs,
Viswanathan adds that 24m new battery design ould do the same sort of disruption to lithium ion batteries manufacturing as
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