noninvasive 3d biomedical imaging photonic chips aerospace photonics micromachines laser tweezing the process of using lasers to trap tiny particles.
nanometer particles with the ability to absorb light and re-emit it with well-defined colors.
where the particle size determines the color of the emitted light. The new strategy relies on a completely different physical mechanism;
Further, the exceptional clarity of the transparent silk gels enabled the laser's photons to be absorbed nearly 1 cm below the surface of the gel-more than 10 times deeper than with other materials
This produces almost no neutrons but instead fast, heavy electrons (muons), since it is based on nuclear reactions in ultra-dense heavy hydrogen (deuterium)."
since the neutrons produced by such processes can cause dangerous flash burns, "says Leif Holmlid, Professor Emeritus at the University of Gothenburg.
"A considerable advantage of the fast heavy electrons produced by the new process is that these are charged
The energy in the neutrons which accumulate in large quantities in other types of nuclear fusion is difficult to handle
because the neutrons are charged not. These neutrons are high-energy and very damaging to living organisms,
whereas the fast, heavy electrons are considerably less dangerous.""Neutrons are difficult to slow down or stop and require reactor enclosures that are several metres thick.
Muons-fast, heavy electrons-decay very quickly into ordinary electrons and similar particles. Research shows that far smaller and simpler fusion reactors can be built.
The next step is to create a generator that produces instant electrical energy y
#A new single-molecule tool to observe enzymes at work A team of scientists at the University of Washington
and the biotechnology company Illumina have created an innovative tool to directly detect the delicate, single-molecule interactions between DNA and enzymatic proteins.
The nanoparticle hydrophilic layer essentially locks in the active ingredient, a hydrophobic chemical called padimate O. Some sunscreen solutions that use larger particles of inorganic compounds, such as titanium dioxide or zinc oxide,
"In this work, we have made two major advances--the ability to precisely control the brightness of light-emitting particles called quantum dots,
and tunable number of photons per tagged biomolecule. They are expected also to be used for precise color matching in light-emitting devices and displays,
and for photon-on-demand encryption applications. The same principles should be applicable across a wide range of semiconducting materials."
The scientists developed a nanoscale photodetector that uses the common material molybdenum disulfide to detect optical plasmons--travelling oscillations of electrons below the diffraction limit
rather than solely to the laser's wavelength, demonstrating that the plasmons effectively nudged the electrons in Mos2 into a different energy state."
and deposited metal contacts onto that same end with electron beam lithography. They then connected the device to equipment to control its bias,
the energy was converted into plasmons, a form of electromagnetic wave that travels through oscillations in electron density.
This energy electronically excited an electron once it reached the molybdenum disulfide-covered end effectively generating a current.
Düsseldorf, Mainz, Princeton and Santa barbara, a ring of colloidal particles are localised in optical tweezers and automatically translated on a circular path,
Through optical manipulation the particle ring can be squeezed at will, altering the coupling between the driven and loaded parts of the assembly and providing a clutch-like operation mode."
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,
#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. echnologies 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.
When the electrons are travelling through a magnetic whirl, they feel the canting between the atomic magnets,
or high-energy reservoir of electrons. Lithium can do that, as the charge carrier whose ions migrate into the graphite
which requires transferring polarization from unpaired electrons to protons and then carbon nuclei, using microwaves generated by a gyrotron,
and electrons to read data Scientists from Kiel University and the Ruhr Universität Bochum (RUB) have developed a new way to store information that uses ions to save data
and electrons to read data. This could enable the size of storage cells to be reduced to atomic dimensions.
Standard memory devices are based on electrons which are displaced by applying voltage. The development of ever smaller and more energy-efficient storage devices according to this principle,
"Electrons are roughly 1000 times lighter than ions and so they move much more easily under the influence of an external voltage.
while the electrons remain mobile and can be used to read the storage status."The trick:
"The tunnel effect enables us to move electrons through the ultra-thin layer with very little energy,
and electrons, on the other hand, at voltages far below one volt. This way, ions can be used specifically for storing and electrons specifically for reading data.
The researchers also reported that their research had another very interesting element. The new resistance-based storage devices could even simulate brain structures.
which involves the gaining of electrons. The reduced-graphene oxide-coated materials were found to be particularly sensitive to detecting nitrogen dioxide
Ultrafast electron pulses are one tool scientists use to probe the atomic world. When the pulses hit the atoms in a material, the electrons scatter like a wave.
By setting up a detector and analyzing the wave interference pattern, scientists can determine information like the distance between atoms.
Conventional electron pulse technology uses a static magnetic field to compress the electrons transversely. However, the static field can interfere with the electron source and the sample and lead to temporal distortion of the electron pulses--both
of which can lead to lower quality images. To avoid the problems associated with static field compression the MIT
and SIMTECH team proposed the first all-optical scheme for compressing electron pulses in three dimensions
In the scheme, laser pulses, functioning as three-dimensional lenses in both time and space, can compress electron pulses to attosecond durations and sub-micrometer dimensions,
providing a new way to generate ultrashort electron pulses for ultrafast imaging of attosecond phenomena."
one can compress electron pulses by as much as two to three orders of magnitude in any dimension or dimensions with experimentally achievable laser pulses.
This translates, for instance, to reducing the duration of an electron pulse from hundreds of femtoseconds to sub-femtosecond scales,
Compressing Electron Pulses In time and Space Short pulse durations are critical for high temporal resolution in ultrafast electron imaging techniques.
To ensure that the electron pulse arrives at the sample or detector with the desired properties in spite of inter-electron repulsion
ultrafast electron imaging setups usually require means to compress the electron pulse both transversely and longitudinally.
which are coils of wire that create uniform magnetic fields, to focus the electron beams. The use of static field elements can lead to the undesirable presence of static magnetic fields on the electron source (cathode)
and the sample and can also cause temporal distortions when transporting ultrashort electron pulses. To solve these problems,
Wong's team conceived an all-optical scheme that focuses electron pulses in three dimensions by using a special type of laser mode with an intensity"valley"(or minimum) in its transverse profile,
which is technically known as a"Hermite-Gaussian optical mode.""The pulsed laser modes successively strike the moving electrons at a slanting angle, fashioning a three-dimensional trap for the electrons."
"To compress the electron pulse along its direction of travel, for instance, the laser-electron interaction accelerates the back electrons
and decelerates the front electrons. As the electrons propagate, the back electrons catch up with the front electrons, leading to temporal compression of the electron pulse,
"Wong explained. The force that the optical field exerts on the electrons is called the optical ponderomotive force,
a time-averaged force that pushes charged particles in a time-varying field towards regions of lower intensity."
"Just as conventional lenses can be used to focus a light beam, our configuration can be used to focus an electron beam.
In our case, however, we can perform the focusing not only in the dimensions perpendicular to the direction of travel,
but also in the dimension parallel to the direction of travel. Hence, the entire setup can be seen as a spatiotemporal lens for electrons,
"Wong said. By modeling the fields with exact solutions of Maxwell equations and solving the Newton-Lorentz equation,
which together describe classical optical and electromagnetic behavior, Wong and his collaborators have analytically and numerically demonstrated the viability of their scheme.
Among their findings is the fact that the longitudinal compression is sensitive to the laser pulse incidence angle,
which is a function of the electron pulse velocity for optimal performance. A major cost-saving feature in the proposed scheme is the fact that a single optical pulse can be used to implement a succession of compression stages.
Since the scheme allows laser pulses to be recycled for further compression of the same electron pulse (not restricted to the same dimension),
Besides being of great interest in ultrafast electron imaging for compressing both single-and multi-electron pulses
the proposed scheme is potentially useful for focusing other particles such as accelerated protons and neutral atoms.
Broader applications include the creation of flat electron beams and the creation of ultrashort electron bunches for coherent terahertz emission in free-electron based terahertz generation schemes,
"Graphene, a one-atom-thick, two-dimensional sheet of carbon atoms, is known for moving electrons at lightning speed across its surface without interference.
and stop electrons at will via bandgaps, as they do in computer chips. As a semimetal, graphene naturally has no bandgaps,
a technique using electrons (instead of light or the eyes) to see the characteristics of a sample,
Data gathered from the electron signatures allowed the researchers to create images of the material's dimensions and orientation.
and extent to which electrons scattered throughout the material.""We're looking at fundamental physical properties to verify that it is, in fact,
and have developed the world's most efficient quantum bits in silicon using either the electron or nuclear spins of single phosphorus atoms.
A series of electron micrographs showing the barrel-shaped helicase with several components of the replisome:
The electron micrographs show that the replisome is a 20-nanometer sized nanomachine. click on image to enlarge) To test these assumptions,
right, revealed by electron micrograph images in the current study. Prior to this study scientists believed the two polymerases (green) were located at the bottom
and ability to transport electrons at high speed, but it is also a highly sensitive gas sensor.
Because pore opening disrupts the flow of electrons and protons across the mitochondrial membranes which normally sustains energy production,
-or neutron scattering-based techniques to study them. A different approach The de Pablo group took a completely different approach.
or neutron scattering would be very useful.?Carla Reiter a
#Artificial intelligence System Solves SAT Geometry As well as 11th Graders The Allen Institute for Artificial intelligence (AI2) and University of Washington researchers have created an artificial intelligence (AI) system that can solve SAT geometry questions as well as the average American 11th-grade student, a breakthrough in AI research.
Nothing about the particles told the researchers what the voltages should be, however. They started with random combinations of voltages and learned
The clump of particles has to be cooled to just 0. 3°C above absolute zero, but making the particles smaller would allow the working temperature to rise.
Van der Wiel says there is no reason the approach couldn work at room temperature. Van der Wiel hopes the research will lead to specialised processors that can solve problems such as pattern recognition
Nothing about the particles told the researchers what voltages to try, however. They started with random values and learned
because very small particles then slip out of it like fish through a net. The use of 3d printing to make working tissue
what path photons take down the fibre, and how they interfere with each other, Carpenter says. Finally, they created a light pulse with the exact cross-section needed to counteract the distortion
They manufactured the implant with a $1. 3 million metal printer at a government-run lab. The printer uses an electron beam to melt titanium powder,
The paper states,-rays radiated by relativistic electrons driven by well-controlled high-power lasers offer a promising route to a proliferation of this powerful imaging technology.
and wiggles electrons, giving rise to a brilliant kev X-ray emission. his so-called betatron radiation is emitted in a collimated beam with excellent spatial coherence and remarkable spectral stability.
The X-rays required were generated by electrons that were accelerated to nearly the speed of light over a distance of approximately one centimeter by laser pulses lasting around 25fs.
and their electrons like a ship through water, producing a wake of oscillating electrons. This electron wave creates a trailing wave-shaped electric field structure on which the electrons surf and by
which they are accelerated in the process. The particles then start to vibrate, emitting X-rays. Each light pulse generates an X-ray pulse.
The X-rays generated have special properties: a wavelength of approximately 0. 1nm, which corresponds to a duration of only about 5fs,
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
#Laser array on silicon promises new level of photonic integration Scientists in Belgium are claiming a breakthrough advance for integrated photonics by fabricating an array of laser diodes on a large silicon wafer typical
#Chip Simplifies Quantum Optics Experiments A silicon chip that can process photons in an infinite number of ways could speed up development of quantum computing.
The system consists of a cascade of 15 Mach-Zehnder interferometers with 30 thermo-optic phase shifters and 12 single-photon detectors.
Now anybody can run their own experiments with photons, much like they operate any other piece of software on a computer.
#Spinal Neuron Connections Probed with Fluorescence microscopy Using two-photon fluorescence microscopy, researchers have gained new insight into how the spinal cord mediates commands from the brain to get the body moving.
will be used on Rocket Labs Electron orbital launch vehicle, which will get its first test spin later this year.
Rutherford is produced also via electron beam melting, an advanced form of 3d printing. Its engine chamber, injector, turbopumps,
The Rutherford engine will be the main propulsion source for Rocket Labs Electron vehicle which the company hopes to use as a low-cost method for launching satellites and other small payloads of up to 220 pounds into space.
On the most basic level, that means that dissolved salt particles, which have a slight electric charge,
Prions, or roteinaceous infectious particles, are proteins that exist normally in the body but can sometimes cause disease.
and contrast agents to the nanoparticle to track the particle. Or the nanoparticle itself is the image and contrast agent
Her Phd at Purdue University and her research at Boston's Massachusetts institute of technology were dedicated both to studying particle stabilization to avoid clogging arteries with the nanoparticles and drug delivery vehicles;
"Graphene, a one-atom-thick, 2-D sheet of carbon atoms, is known for moving electrons at lightning speed across its surface without interference.
and stop electrons at will via bandgaps, as they do in computer chips. As a semimetal, graphene naturally has no bandgaps,
a technique using electrons (instead of light or the eyes) to see the characteristics of a sample,
Data gathered from the electron signatures allowed the researchers to create images of the material's dimensions and orientation.
and extent to which electrons scattered throughout the material.""We're looking at fundamental physical properties to verify that it is, in fact,
Ultimately, it is these electrons which are transferred to the protons in the water moleculend thereby create elementary hydrogen.
The COFS created in Stuttgart meet all the prerequisites. However the scientists had to add platinum nanoparticles and an electron donor to their powder polymer."
"The platinum nanoparticles work as microelectrodes on which the electrons are transferred from the COF to the protons to form hydrogen,
"says Vijay Vyas, a scientist in the Nanochemistry Research Group at the Stuttgart-based Max Planck Institute for Solid State Research."
"And the electron donor is necessary to remove the residual positive charge on the COF, "Vyas explains.
which absorb electrons meant for conversion. According to researchers, the sample with the solvent additive was consistent throughout
However, the information obtained from the neutron reflectometry will help scientists boost organic solar cell performance, according to ORNL. ptimization of photovoltaic properties provides information to manufacture solar cells with fully controlled morphology
according to the researchers. hat unique about this paper is that we show not the use of metal particles, not the use of metal nanoparticles,
but the use of atoms, Tour said. he particles doing this chemistry are as small as you can possibly Get even particles on the nanoscale work only at the surface,
A Purdue Univ.-led team of researchers observed electrons transition from a topologically ordered phase to a broken symmetry phase."
His team employs novel investigative techniques for the study of electrons freely flowing in ultrapure gallium arsenide semiconductor crystals,
and arsenic atoms that can capture electrons on a 2-D plane. Only a few groups in the world are able to grow the material,
The gallium arsenide crystals grown using the molecular beam epitaxy technique serve as a model platform to explore the many phases that arise among strongly interacting electrons,
but it is worth the effort to discover new phenomena involving the entire sea of electrons acting in concert.
"Material grown by the Manfra group was shown to have an electron mobility measurement of 35 million centimeters squared per volt-second,
"In most materials electrons are restricted very in what they can do because they bump into atomic-level defects that perturb them,
"The material grown by the Manfra group is so pure and free from defects that it gives electrons the freedom to enter into more than 100 different phases,
The extremely low temperature encourages the electrons to enter into exotic states where they no longer obey the laws of single particle physics,
A collective motion of the electrons is then possible that is described by the laws of quantum mechanics
"Imagine eggs in an egg carton as electrons arranged in a certain formation, "he said."
"The eggs are identical just like the electrons are identical particles. If you swap one egg with another,
if you swap two electrons, it causes a change to the entire group and the egg carton enters an entirely different state.
"The team was trying to induce an electron spin transition in this non-Abelian state, but before the desired state was reached,
the electrons spontaneously transitioned into the so-called"stripe"phase that belongs to the traditional, broken symmetry phases group."
but the electrons went from deep in the topological phase too deep in the broken symmetry phase."
These isotopes are distinguished from one another by the number of neutrons in the nucleus, and thus by their mass.
The newly discovered isotopes have fewer neutrons and are lighter than the previously known isotopes of the respective elements.
Due to their low number of neutrons, their structure is very exotic and therefore interesting for the development of theoretical models describing atomic nuclei. hese results really push what we know about nuclear structure to the extreme, neutron-deficient end of the chart of the nuclides,
Shaughnessy said. hen you realize that naturally occurring uranium has 146 neutrons and this new isotope only has 124 neutrons,
it shows how much more we still have yet to learn about nuclear structure and the forces that hold the nucleus together.
Scientists at LLNL have been involved in heavy element research since the Laboratory's inception in 1952 and have been collaborators in the discovery of six elements 113,114 (Flerovium), 115,116 (Livermorium), 117 and 118.
the two nuclei involved exchanged a number of their nuclear building-blocks protons and neutrons. Different isotopes formed as the end products of this exchange.
which an electrode used for splitting water absorbs solar photons while at the same time improving the flow of electrons from one electrode to another.
"Excited electrons When building a sun-capturing electrode, scientists aim to use as much of the solar spectrum as possible to excite electrons in the electrode to move from one state to another,
where they will be available for the water-splitting reaction. Equally important, but a separate problem entirely, the electrons need to move easily from the electrode to a counter-electrode,
creating a flow of current. Until now, scientists have had to use separate manipulations to increase photon absorption
and the movement of electrons in the materials they are testing. Choi and postdoctoral researcher Tae Woo Kim found that
if they heated an electrode made of the semiconducting compound bismuth vanadate to 350 degrees Celsius
The result was a notable increase in both photon absorption and electron transport. What was not clear was exactly how the nitrogen was facilitating the observed changes.
"Galli's team found that these defects enhance the transport of electrons. But more interestingly, they found that the nitrogen that had been incorporated into the compound increased the transport of electrons independent of the defects.
Finally, that nitrogen lowered the energy needed to kick electrons into the state in which they were available to split water.
This meant that more of the solar energy could be used by the electrode.""Now we understand what's going on at the microscopic level,
So there are carbon particles inside the silicone which make it conductive so we can use it for electronics,
and Israel has discovered a novel phase of matter that is characterized by an unusual ordering of electrons. he discovery of this phase was unexpected completely and not based on any prior theoretical prediction.
first consider a crystal with electrons moving around throughout its interior. Under certain conditions, it can be energetically favorable for these electrical charges to pile up in a regular,
In addition to charge, electrons also have a degree of freedom known as spin.?When spins line up parallel to each other,
what if the electrons in a material are ordered not in one of those ways? In other words, what if the order were described not by a scalar or vector but by something with more dimensionality, like a matrix??
Like the cuprates, iridates are electrically insulating antiferromagnets that become increasingly metallic as electrons are added to
where an additional amount of energy is required to strip electrons out of the material. For years, physicists have debated the origin of the pseudogap
and a smaller version, targeted at manipulating particles inside the human body l
#Non-Genetic Cancer Mechanism Found Cancer can be caused solely by protein imbalances within cells, a study of ovarian cancer has found.
however, did not contain glass particles. The aluminium oxide platelets in the second layer were aligned horizontally to the surface of the tooth using the magnet.
and converts to electrons. According to the press release, these electrons are used then to supplement the voltage stored in the lithium-anode portion of the solar battery.
When they tested their solar batteries against conventional lithium-iodine batteries, they charged and discharged them 25 times to see how much electricity they would discharge each round.
and it contains sub-micron particles that pick up amino and fatty acids as well as the shape of the print itself with the aid of a mass spectrometer.
This scans the print with a laser, particles in the powder are ionised vaporised and, and a molecular profile appears.
Specially made synthetic membranes are used to filter out large salt particles and impurities so they can be evaporated away,
because wee hit the limit for how fast electrons can travel between the processor and the memory."
"Making light-based computers isn as simple as replacing electrons with light particles-or photons-in current computers.
the silicon chips we have now still require the photons to be converted back to electrons when the data reaches our computer.
which actually makes it less efficient than if we just used electrons in the first place. Instead, we need to completely redesign the way our computers work,
-which carries the photons to where they need to go.""Think of the waveguide as a kind of miniature fibre optic cable that can carry light:
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