#Building the electron superhighway TV screens that roll up. Roofing tiles that double as solar panels. Sun powered cell phone chargers woven into the fabric of backpacks.
But the basic science of how to get electrons to move quickly and easily in these organic materials remains murky.
what they are calling"an electron superhighway"in one of these materials--a low-cost blue dye called phthalocyanine--that promises to allow electrons to flow faster and farther in organic semiconductors Their discovery,
"Roughly speaking, an exciton is displaced a electron bound together with the hole it left behind.
the UVM team was able to observe nanoscale defects and boundaries in the crystal grains in the thin films of phthalocyanine--roadblocks in the electron highway."
"We have discovered that we have hills that electrons have to go over and potholes that they need to avoid,
"these stacked molecules--this dish rack--is the electron superhighway.""Though excitons are charged neutrally --and can't be pushed by voltage like the electrons flowing in a light bulb--they can, in a sense, bounce from one of these tightly stacked molecules to the next.
This allows organic thin films to carry energy along this molecular highway with relative ease,
Wave-particle dualism with large molecules The virtual laboratories provide an insight into the fundamental understanding and into the applications of quantum mechanics with macromolecules and nanoparticles.
In recent years, the real-life versions of the experiments verified the wave-particle dualism with the most complex molecules to date.
#Tiny silica particles could be used to repair damaged teeth, research shows Researchers at the University of Birmingham have shown how the development of coated silica nanoparticles could be used in restorative treatment of sensitive teeth
The study, published in the Journal of Dentistry, shows how sub-micron silica particles can be prepared to deliver important compounds into damaged teeth through tubules in the dentine.
The tiny particles can be bound to compounds ranging from calcium tooth building materials to antimicrobials that prevent infection.
with the particles acting like seeds for further growth that would close the tubules. Previous attempts have used compounds of calcium fluoride, combinations of carbonate-hydroxypatite nanocrystals and bioactive glass,
However, the Birmingham team turned to sub-micron silica particles that had been prepared with a surface coating to reduce the chance of aggregation.
When observed using high definition SEM (Scanning Electron Microsopy the researchers saw promising signs that suggested that the aggregation obstacle had been overcome.
"These silica particles are available in a range of sizes, from nanometre to sub-micron,
""We tested a number of different options to see which would allow for the highest level particle penetration into the tubules,
and then see how effective the particles are blocking the communication with the inside of the tooth.
Deleon and her UD team have identified particles in the secretions from the fallopian tube that help the sperm get ready for its all-important drive into the end zone.
supplies beams from exotic elementary particles called muons, which can be used to study nanomagnetic properties. The project took place in collaboration with a research group headed by Stephen Lee from the University of St andrews, Scotland n
which a beam of electrons smaller than the size of a hydrogen atom is scanned over a sample
and measures how many electrons interact with the atoms at each scan position. The method reveals the atomic structure of materials
because different arrangements of atoms cause electrons to interact in different ways. However, scanning transmission electron microscopes only produce two-dimensional images.
The downside of this technique is repeated that the electron beam radiation can progressively damage the sample.
thanks to the electron beam energy being kept below the radiation damage threshold of tungsten. Miao and his team showed that the atoms in the tip of the tungsten sample were arranged in nine layers, the sixth
and cools it in a way that allows it to convert more photons into electricity. The work by Shanhui Fan, a professor of electrical engineering at Stanford, research associate Aaswath P. Raman and doctoral candidate Linxiao Zhu is described in the current issue of Proceedings of the National Academy
the less efficient they become at converting the photons in light into useful electricity. The Stanford solution is based on a thin,
"We call this a smart particle, "said James Swartz, the professor of chemical engineering and of bioengineering at Stanford who led the study."
"Using the smart particle for immunotherapy would involve tagging its outer surface with molecules designed to teach the body's disease-fighting cells to recognize
It will require much more effort to accomplish the second goal--packing tiny quantities of medicines into the smart particles,
delivering the particles to and into diseased cells, and engineering them to release their payloads.'
"But I believe we can use this smart particle to deliver cancer-fighting immunotherapies that will have minimal side effects."
"Dr. Swartz and colleagues have done a remarkable job of stabilizing viruslike particles and re-engineering their surface."
The new paper describes how the Stanford team designed a viruslike particle that is only a delivery vehicle with no infectious payload.
Swartz said the next step is to attach cancer tags to the outside of this smart particle,
"or transferred quantum information carried in light particles over 100 kilometers (km) of optical fiber, four times farther than the previous record.
The achievement was made possible by advanced single-photon detectors designed and made at NIST.""Only about 1 percent of photons make it all the way through 100 km of fiber,
"NIST's Marty Stevens says.""We never could have done this experiment without these new detectors,
when in a sequence of time slots a single photon arrives. The teleportation method is novel in that four of NIST's photon detectors were positioned to filter out specific quantum states.
The detectors rely on superconducting nanowires made of molybdenum silicide. They can record more than 80 percent of arriving photons,
revealing whether they are in the same or different time slots each just 1 nanosecond long.
which harness the science of the very small--the strange behaviour of subatomic particles--to solve computing challenges that are beyond the reach of even today's fastest supercomputers.
"We've morphed those silicon transistors into quantum bits by ensuring that each has only one electron associated with it.
We then store the binary code of 0 or 1 on the'spin'of the electron,
which is associated with the electron's tiny magnetic field, "he added. Dzurak noted that that the team had patented recently a design for a full-scale quantum computer chip that would allow for millions of our qubits,
'Electrons have a spin, and thus they interact with magnetic structures, 'says Prof. Stefan Heinze from the University of Kiel.
When the electrons are travelling through a magnetic whirl, they feel the canting between the atomic magnets,
as the scientists surrounding DESY's Franz Kärtner from the Center For free-Electron Laser Science (CFEL) point out.
The physicists fired fast electrons into the miniature accelerator module using a type of electron gun provided by the group of CFEL Professor Dwayne Miller, Director at the Max Planck Institute for the Structure and Dynamics
The electrons were accelerated then further by the terahertz radiation fed into the module. This first prototype of a terahertz accelerator was able to increase the energy of the particles by seven kiloelectronvolts (kev."
"This is not a particularly large acceleration, but the experiment demonstrates that the principle does work in practice,
and as a means of building compact X-ray lasers and electron sources for use in materials research,
experimental free-electron X-ray laser (XFEL) on a laboratory scale using terahertz technology. This project is supported by a Synergy Grant of the European Research Council.
So-called free-electron lasers (FELS) generate flashes of laser light by sending high-speed electrons from a particle accelerator down an undulating path,
"Hasan's method, developed at the University's Nanoscience Centre, works by suspending tiny particles of graphene in a'carrier'solvent mixture,
Light goes infinitely fast with new on-chip material Electrons are so 20th century. In the 21st century, photonic devices,
or waveguide to emit photons which are always in phase with one another, "said Philip Munoz,
and infinitely long, enabling even distant particles to be entangled.""""This on-chip metamaterial opens the door to exploring the physics of zero index
a change in electrical resistance, also known as magnetoresistance, occurs as the electrons are deflected. The discovery of magnetoresistance paved the way for magnetic field sensors used in hard disk drives and other devices,
The particles, described in Nature Communications, are enhanced an version of a naturally occurring, weakly magnetic protein called ferritin."
This eliminates the need to tag cells with synthetic particles and allows the particles to sense other molecules inside cells.
The paper's lead author is former MIT graduate student Yuri Matsumoto. Other authors are graduate student Ritchie Chen and Polina Anikeeva, an assistant professor of materials science and engineering.
Magnetic pull Previous research has yielded synthetic magnetic particles for imaging or tracking cells, but it can be difficult to deliver these particles into the target cells.
In the new study Jasanoff and colleagues set out to create magnetic particles that are encoded genetically.
With this approach, the researchers deliver a gene for a magnetic protein into the target cells,
This is beneficial because it prevents direct contact between the tissue and the silver particles, which can be exposed toxic
the innovation harnesses tiny electron waves called plasmons. It a step towards enabling computers to process information hundreds of times faster than today machines.
When light waves interact with electrons on a metal surface, strong fields with dimensions far smaller than the wavelength of the original light can be createdlasmons.
Analysis of the data also indicates that the dust grains orbiting the star are sorted by particle size,
and protons can flow in a controlled way across the lipid-membrane barrier around the cell-like vesicle.
and to form two special pockets for binding zinc ions and protons along the cavity within the bundle.
One conformation opens up the pocket near one side of the membrane to grab zinc ions or protons.
while protons traveled the other direction. esigning this protein is an amazing accomplishment made possible by bringing together scientists with complementary areas of expertise,
using protons. One can imagine in a totally noncellular case that one could potentially harvest this kind of pumping to create things like batteries.
nanowires harvest solar energy and deliver electrons to bacteria, where carbon dioxide is reduced and combined with water for the synthesis of a variety of targeted, value-added chemical products.
photo-excited electron#hole pairs are generated in the silicon and titanium oxide nanowires, which absorb different regions of the solar spectrum.
The photo-generated electrons in the silicon will be passed onto bacteria for the CO2 reduction while the photo-generated holes in the titanium oxide split water molecules to make oxygen.
the Berkeley team used Sporomusa ovata, an anaerobic bacterium that readily accepts electrons directly from the surrounding environment
the flow of electrons generated projects the molecules of interest toward the target area. To enable validation of this new technique,
light photo-catalysts and ferroelectric materials in electronics. nalogous to the best metallic conductors such as copper or silver where the current is transported by electron, in d-Bismuth oxide
such as photolithography and electron-beam lithography. By comparison, the smallest nanogaps that can be generated using the standard methods are 100 nm wide. aking a nanogap is interesting from a philosophical standpoint,
Scanning electron micrographs of the structures reveal extremely small nanogaps between the gold layers. Nanogap applications One potential application for this technology is in ultra-sensitive detection of single molecules,
or a lot of crystal particles all pressed together. Whereas with glass, crack that forms on the surface will go all the way through,
This ixie dustis meant to melt and ubricate the powder particles, so there less friction,
This light bounces off air molecules and small particles such as dust, ice and droplets of water in the atmosphere.
The movement of the air molecules, particles or droplets cause this backscattered light to change frequencies slightly.
to instantly identify a single virus particle or protein. A microscopic tool, more than 1000 times thinner than the width of a single human hair, uses vibrations to simultaneously reveal the mass and the shape of a single molecule a feat
say, a virus or a bacteria particle. In mass spectrometry, molecules are ionised (or electrically charged)
and also its tone. e can analyse this measurement to get both the mass and shape of the attached particle,
can we design a particle that can sense its environment with no neural system or biological parts.
The particles encircled the tip of the pipette at a distance where their propulsion was cancelled out by the velocity of the flow.
and predicts the stagnation point where the beads accumulate. hat is really cool is that the mechanism we used to get the particles to go upstream actually exists in nature
and it the way many microbes find food. f you can design particles that can feel their environment
you could think of particles that swim against the blood stream to fix clogged arteries, Palacci says,
& Photon Science and LLNL Physical and Life sciences (PLS) Directorate. lot of unique engineering efforts were put into this,
and KBO 3, designed for hardened X-ray cameras for use in high-neutron-yield experiments,
The new technology, developed by a team of scientists from Argonne Center for Nanoscale Materials (CNM) and the Advanced Photon Source (APS), involves a small microelectromechanical system (MEMS) mirror only
The MEMS device acts as an ultrafast mirror reflecting X-rays at precise times and specific angles. xtremely compact devices such as this promise a revolution in our ability to manipulate photons coming from synchrotron light sources,
Associate Laboratory Director for Photon Sciences and Director of the Advanced Photon Source. his is a premier example of the innovation that results from collaboration between nanoscientists and X-ray scientists.
more elaborate X-ray optical schemes for studying the structure and dynamics of matter at atomic length and time scales, added Edgar Weckert, the director of photon science at DESY,
These include newly planned light source facilities such as the Advanced Photon Source Upgrade. uch small sources
these particles tend to rapidly aggregate in physiological conditions, rendering them too large to penetrate the mesh of airway mucus. For its design,
from the prediction of chemical properties studied in computational chemistry applications to the identification of particles for high-energy physics experiments. i
The work is centered on enhancing the arrangement of colloidsmall particles suspended within a fluid medium.
with these particles attaching to each other in ways that produce chaotic or inflexible configurations. The NYU team developed a new method to apply DNA coating to colloids
However, the method, at that point, could manipulate only one type of particle. In the JACS study, the research team shows the procedure can handle five additional types of materialsnd in different combinations.
you need to have the ability for a particle to move around and find its optimal position,
Working at the Center for Nanoscale Materials (CNM) and the Advanced Photon Source (APS), two DOE Office of Science User Facilities located at Argonne,
when hit with an electron beam. Equally importantly, they have discovered how and why it happens.
When floated on water the particles form a sheet; when the water evaporates, it leaves the sheet suspended over a hole. t almost like a drumhead,
direction using an electron beam because two sides of the membrane are different. Image credit:
When the electron beam hits the molecules on the surface it causes them to form an additional bond with their neighbors,
They envision zapping only a small part of the structure with the electron beam, designing the stresses to achieve particular bending patterns. ou can maybe fold these things into origami structures and all sorts of interesting geometries,
and particles from the cell surface into the cell. If this doesn work, the function of the cell is disturbed,
Meteors (popularly known as hooting stars are the result of small particles, some as small as a grain of sand, entering the Earth atmosphere at high speed.
these particles heat the air around them, causing the characteristic streak of light seen from the ground.
Superfluids are thought to flow endlessly, without losing energy, similar to electrons in a superconductor. Observing the behavior of superfluids
Atoms of rubidium are known as bosons, for their even number of nucleons and electrons. When cooled to near absolute zero
bosons form what called a Bose-Einstein condensate a superfluid state that was discovered first co by Ketterle,
and for which he was awarded ultimately the 2001 Nobel prize in physics. After cooling the atoms,
which mimics the regular arrangement of particles in real crystalline materials. When charged particles are exposed to magnetic fields,
their trajectories are bent into circular orbits, causing them to loop around and around. The higher the magnetic field, the tighter a particle orbit becomes.
However, to confine electrons to the microscopic scale of a crystalline material, a magnetic field 100 times stronger than that of the strongest magnets in the world would be required.
The group asked whether this could be done with ultracold atoms in an optical lattice. Since the ultracold atoms are charged not,
as electrons are, but are instead neutral particles, their trajectories are unaffected normally by magnetic fields. Instead, the MIT group came up with a technique to generate a synthetic
ultrahigh magnetic field, using laser beams to push atoms around in tiny orbits, similar to the orbits of electrons under a real magnetic field.
In 2013, Ketterle and his colleagues demonstrated the technique, along with other researchers in Germany, which uses a tilt of the optical lattice
In this scenario, atoms could only move with the help of laser beams. ow the laser beams could be used to make neutral atoms move around like electrons in a strong magnetic field
or loop around, in a radius as small as two lattice squares, similar to how particles would move in an extremely high magnetic field. nce we had the idea,
Recently, researchers at Oxford university Department of Engineering science have been investigating mart gelsthat can switch from a stable gel to a liquid suspension of very small particles (a ol.
The scattering photons from the laser bounce off obstacles and make their way back to sensors in the camera.
The dimensions of that unseen space are recreated then based on the time stamp of the photons that scatter back to the camera.
or brain region. e want to precisely control where photons are being sent to activate different cells, Newman said. ptogenetics allows genetic specification
#Scientists queezelight one particle at a time A team of scientists has measured successfully particles of light being queezed in an experiment that had been written off in physics textbooks as impossible to observe.
In the journal Nature, a team of physicists report that they have demonstrated successfully the squeezing of individual light particles,
or photons, using an artificially constructed atom, known as a semiconductor quantum dot. Thanks to the enhanced optical properties of this system and the technique used to make the measurements,
That meant we were able to reach the necessary conditions to observe this fundamental property of photons
and prove that this odd phenomenon of squeezing really exists at the level of a single photon.
what photons should do. Like a lot of quantum physics the principles behind squeezing light involve some mind-boggling concepts.
It begins with the fact that wherever there are light particles, there are also associated electromagnetic fluctuations. This is a sort of static
It looks like there are zero photons present, but actually there is just a tiny bit more than nothing.
This excited the quantum dot and led to the emission of a stream of individual photons.
This states that in any situation in which a particle has linked two properties, only one can be measured
Atature added that the main point of the study was simply to attempt to see this property of single photons,
red) and probed the laser-induced structural changes with a subsequent electron pulse (probe pulse, blue).
The electrons of the probe pulse scatter off the monolayer atoms (blue and yellow spheres)
It was made possible with SLAC instrument for ultrafast electron diffraction (UED), which uses energetic electrons to take snapshots of atoms
and molecules on timescales as fast as 100 quadrillionths of a second. his is published the first scientific result with our new instrument,
This animation explains how researchers use high-energy electrons at SLAC to study faster-than-ever motions of atoms and molecules relevant to important materials properties and chemical processes.
Researchers have used SLAC experiment for ultrafast electron diffraction (UED), one of the world fastest lectron cameras,
which were prepared by Linyou Cao group at North carolina State university, into a beam of very energetic electrons.
The electrons, which come bundled in ultrashort pulses, scatter off the sample atoms and produce a signal on a detector that scientists use to determine where atoms are located in the monolayer.
This technique is called ultrafast electron diffraction. Illustrations (each showing a top and two side views) of a single layer of molybdenum disulfide (atoms shown as spheres.
hollow particles that are secreted from many types of cells. They contain functional proteins and genetic materials and serve as a vehicle for communication between cells.
Virendra Singh and Thomas Bougher constructed devices that utilize the wave nature of light rather than its particle nature.
enough to drive electrons out of the carbon nanotube antennas when they are excited by light. In operation, oscillating waves of light pass through the transparent calcium-aluminum electrode
allowing electrons generated by the antenna to flow one way into the top electrode. Ultra-low capacitance, on the order of a few attofarads, enables the 10-nanometer diameter diode to operate at these exceptional frequencies. rectenna is basically an antenna coupled to a diode
#Physicists turn toward heat to study electron spin The quest to control and understand the intrinsic spin of electrons to advance nanoscale electronics is hampered by how hard it is to measure tiny, fast magnetic devices.
Applied physicists at Cornell offer a solution: using heat, instead of light, to measure magnetic systems at short length and time scales.
Why the interest in electron spin? In physics, electron spin is established the well phenomenon of electrons behaving like a quantum version of a spinning top,
and the angular momentum of these little tops pointing por own. An emerging field called spintronics explores the idea of using electron spin to control
and store information using very low power. Technologies like nonvolatile magnetic memory could result with the broad understanding and application of electron spin.
Spintronics, the subject of the 2007 Nobel prize in Physics, is already impacting traditional electronics, which is based on the control of electron charge rather than spin. irect imaging is really hard to do,
Fuchs said. evices are tiny, and moving really fast, at gigahertz frequencies. Wee talking about nanometers and picoseconds.
or high-energy reservoir of electrons. Lithium can do that, as the charge carrier whose ions migrate into the graphite
Hasan method, developed at the University Nanoscience Centre, works by suspending tiny particles of graphene in a arriersolvent mixture,
They capitalised on improvements made at the LMB to a high-powered imaging technique known as single particle cryo-electron microscopy.
Single particle cryo-electron microscopy preserves the ribosomes at sub-zero temperatures to allow the collection
The technique has been refined in the MRC Laboratory of Molecular biology by the development of new irect electron detectorsto better sense the electrons
like a dust particle, to start the process of nucleation, the bubbles formed by boiling water also require nucleation.
we needed to develop a particle that did the same job but was only 6 nanometers in size.
the particle had to pack in the light sensitivity chemical, an amino acid that causes it to be absorbed only by a specific type of heart muscle cells,
and synthesized a star-shaped particle made of polyethylene glycol (PEG) widely used, FDA-approved material. The particle has eight nanoscale tentacles,
offering plenty of points to attach the chemicals needed for the process. The particle was tested by Uma Mahesh Reddy Avula
M d.,lead study author and a research lab specialist in internal medicine. his cell-selective therapy may represent an innovative concept to overcome some of the current limitations of cardiac ablation,
They conducted initial experiments using noninfectious viral-like particles or VLPS, the production of which is orchestrated by the virusmatrix protein and
and then determined the structure employing synchrotron protein crystallography at the Advanced Photon Source, a DOE Office of Science User Facility (both at Argonne).
particles that tightly bundle DNA to fit it into a cell nucleus. These must be dislodged
which exert powerful magnetic fields to compress high-temperature plasmaoiling balls of charged particles that fuse to form helium, releasing large amounts of energy in the process.
is bringing the principles of high-energy particle accelerators, such as the Large hadron collider, to bear on the problems of fusion reactors.
The plasma is sustained by the injection of high-energy particles from accelerators. The challenge for Tri Alpha design, says Binderbauer,
The researchers also envision a liquid lanketsurrounding the plasma that will absorb neutrons without damage
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