The beams of light emanating from the fluorescence molecules can be measured through the top of the mice's skulls.
Researchers have built now a working tractor beam that uses high-amplitude sound waves to generate an acoustic hologram
The team used a red dye called ruthenium to tune the wavelength of light it captures
-and put on a very pretty blue light show to boot. While levitation may sound like it belongs in the realm of fantasy,
what surprised the team most of all was the blue light emission, seeing as they were only using a relatively low 50 volts.
the electromagnetic radiation that makes up these signals is blocked by something you. Yep, our bodies get in the way of the data transmissions,
This scans the print with a laser, particles in the powder are ionised vaporised and, and a molecular profile appears.
but theye also an ongoing field of interest to scientific researchers, who are continually working on ways to manipulate how objects interact with light to see
and hide it from detection via visible light. The cloak which at present is only capable of making microscopic objects invisible,
and when done so, manages to mask their 3d shape by reflecting light waves. his is the first time a 3d object of arbitrary shape has been cloaked from visible light,
or curve the reflection of light via their physical structure rather than their chemical composition, essentially rendering objects optically undetectable.
When light falls on the activated cloak, its array of nanoantennae distort the usual reflection of light from the object underneath,
#New light-based memory chip is the first ever to permanently store data Scientists in the UK have developed the first ever memory chip that entirely light-based
"But we think using light can significantly speed this up.""Making light-based computers isn as simple as replacing electrons with light particles-or photons-in current computers.
running them on light instead of electricity, and this new light-based computer chip brings us one step closer to that goal.
Known as photonic memory, light-based memory is not a new concept, but it posed quite a challenge to engineers in the past.
Not only have previous attempts at light-based computer chips turned out to be quite volatile, theye all required power to store data,
pulses of a laser can be sent down the guide, where they can interact with the GST
Publishing in Nature Photonics this week, the team explained how they could send intense pulses of light through the waveguide to change the state of the GST,
a much lower intensity pulse of light is sent through the waveguide, and the amount of light that transmitted from one end to the other will depend on
so their light-based memory chips can directly interact with the other components using light, rather than electrical signals."
Huo and her team at UCF's Nanoscience Technology Center developed a technique known as nanoparticle-enabled dynamic light scattering assay (Nanodlsay) to measure the size of the particles by analyzing the light they throw off.
The new device, called a biophotonic laser-assisted surgery tool, or BLAST, is a silicon chip with an array of micrometer-wide holes,
Researchers use a laser pulse to heat the titanium coating, which instantly boils the water layer adjacent to parts of the cell.
A laser can scan the entire silicon chip in about 10 seconds. Chiou said the key to the technique's success is the instantaneous and precise incision of the cell membrane."
"An aerial's size is determined by the wavelength associated with the transmission frequency of the application,
Most of what we know about electromagnetic radiation comes from theories first proposed by James Clerk Maxwell in the 19th century,
which state that electromagnetic radiation is generated by accelerating electrons. However, this theory becomes problematic when dealing with radio wave emission from a dielectric solid, a material
and the generation of electromagnetic radiation. The electromagnetic radiation emitted from dielectric materials is due to accelerating electrons on the metallic electrodes attached to them
as Maxwell predicted, coupled with explicit symmetry breaking of the electric field.""If you want to use these materials to transmit energy,
and"in the default mode, the light is red.""But when a growth factor switches on a receptor, special enzymes change the light embedded in the membrane from red to green.
Then, after the signal is transmitted further into the cell's interior, it is time to switch the signal back to red.
#Versatile switch for light-controlled cells: The structure of the light-driven ion pump KR2 may provide a blueprint for new optogenetic tools In 2013,
scientists made an unexpected discovery while investigating the marine bacterium Krokinobacter eikastus. In its cellular membrane, the bacterium had a previously unknown type of ion transporter.
When exposed to light, these proteins allow charged particles to flow into the cell or transport them outside the cell.
but also one of the mutations seemed to turn KR2 into a light-driven potassium pump--the first of its kind.
With a light-activated, active potassium pump this process could be controlled precisely.""This would make KR2 a very effective off-switch for neurons.
"In combination with the light-activated Channelrhodopsin 2, which is used in labs worldwide as a molecular off-switch,
The scientists studied light scattering from a glass cylinder filled with water. In essence such an experiment represents a two-dimensional analog of a classical problem of scattering from a homogeneous sphere (Mie scattering), the solution to
which is related to the localization of light inside the cylinder, and nonresonant, which is characterized by smooth dependence on the wave frequency.
Metamaterials are capable of changing the direction of light in exotic ways, including making light curve around the cloaked object.
the researchers describe a smartphone-based device that uses the kind of technology used to make holograms to collect detailed microscopic images for digital analysis of the molecular composition of cells and tissues."
"The device the team has developed--called the D3 (digital diffraction diagnosis) system--features an imaging module with a battery-powered LED light clipped onto a standard smartphone that records high-resolution imaging data with its camera.
the presence of specific molecules is detected by analyzing the diffraction patterns generated by the microbeads.
The use of variously sized or coated beads may offer unique diffraction signatures to facilitate detection.
#Graphene pushes the speed limit of light-to-electricity conversion ICFO researchers Klaas-Jan Tielrooij, Lukasz Piatkowski,
have demonstrated now that a graphene-based photodetector converts absorbed light into an electrical voltage at an extremely high speed.
The new device that the researchers developed is capable of converting light into electricity in less than 50 femtoseconds (a twentieth of a millionth of a millionth of a second.
To do this, the researchers used a combination of ultrafast pulse-shaped laser excitation and highly sensitive electrical readout.
As Klaas-Jan Tielrooij comments,"the experiment uniquely combined the ultrafast pulse shaping expertise obtained from single molecule ultrafast photonics with the expertise in graphene electronics.
Thus, the energy absorbed from light is efficiently and rapidly converted into electron heat. Next, the electron heat is converted into a voltage at the interface of two graphene regions with different doping.
thus enabling the ultrafast conversion of absorbed light into electrical signals. As Prof. van Hulst states"
Koppens comments,"Graphene photodetectors keep showing fascinating performances addressing a wide range of applications
#Protein finding can pave way for improved treatment of malignant melanoma New research now demonstrates that the presence of the protein megalin in a malignant melanoma is an indicator of cancer cells that are particularly aggressive.
#Shape-shifting molecule tricks viruses into mutating themselves to death A newly developed spectroscopy method is helping to clarify the poorly understood molecular process by
Supporting data were collected with two-dimensional infrared spectroscopy, an advanced laser technique that combines ultrafast time resolution with high sensitivity to chemical structure.
Critical tool"Two-dimensional infrared spectroscopy will be critical on the path ahead. It lets us look at the structures that exist in aqueous solution,
With 2d infrared spectroscopy, the UCHICAGO team was able to distinguish between the two structures.
The hints given us by the spectroscopy guide us toward even better mutagenic molecules, "Essigmann said.
When a beam of light then hits the molecule, it switches from its open to its closed state, resulting in a flowing current."
which we have used the light beam, "says Dr. Erbe, pleased with the results.""We have characterized also the molecular switching mechanism in extremely high detail,
The diarylethene molecule contact using electron-beam lithography and the subsequent measurements alone lasted three long years.
and other collaborators to perform experiments with a state-of-the-art transmission X-ray microscope at the National Synchrotron Light source at Brookhaven.
National Synchrotron Light source, Brookhaven National Laboratory, and supported by the U s. Department of energy Basic energy Sciences and a seed grant from the Wisconsin Energy Institute.
Experts say that recent advances in LED TECHNOLOGY have made it possible to modulate the LED light more rapidly,
opening the possibility of using light for wireless transmission in a"free space optical communication system.""In addition to improving the experience for users,
and creates an invisible cone of light about one meter square in which the data can be received.
The receivers are small photodiodes that cost less than a dollar each and could be connected through a USB port for current systems,
#Printing silicon on paper, with lasers Recently, a group of researchers at Delft University of Technology,
to be produced directly on a substrate from liquid silicon ink with a single laser pulse--potentially ousting its pale usurpers.
Then we annealed the layer with an excimer laser a conventional tool used for manufacturing smartphone displays.
The laser blast only lasted a few tens of nanoseconds, leaving the paper completely intact. In testing its conductive performance,
Ishihara and his colleagues found that thin-film transistors using the laser-printed layer exhibited mobilities as high as those of conventional poly-silicon conductors.
An efficient terahertz emission from two-dimensional arrays of gold split-ring resonator metamaterials was discovered as a result of excitation by a near-infrared pulsed laser.
when a two-dimensional array of nanometer-sized gold metamaterial resonators is illuminated by a tunable near-infrared femtosecond laser,
with wavelengths matching the magnetic resonance of the metamaterial, a strong broadband of terahertz electromagnetic waves is emitted.
Detailed analysis of the directionality and polarization of the emitted radiation reveals the fundamental nature of this efficient wavelength conversion.
#Generating broadband terahertz radiation from a microplasma in air Researchers have shown that a laser-generated microplasma in air can be used as a source of broadband terahertz radiation.
They demonstrate that an approach for generating terahertz waves using intense laser pulses in air can be done with much lower power lasers, a major challenge until now.
They have exploited the underlying physics to reduce the necessary laser power for plasma generation. Researchers at the University of Rochester's Institute of Optics have shown that a laser-generated microplasma in air can be used as a source of broadband terahertz radiation.
In a paper published this week in Optica Fabrizio Buccheri and Xi-Cheng Zhang demonstrate that an approach for generating terahertz waves using intense laser pulses in air--first pioneered in 1993--can be done with much lower power lasers, a major challenge until now.
Ph d. student and lead author Buccheri explains that they exploited the underlying physics to reduce the necessary laser power for plasma generation.
He adds that it could potentially be improved for applications in the monitoring of explosives or drugs.
a form of electromagnetic radiation named after its frequency, can be divided into two categories: imaging and spectroscopy.
Imaging using terahertz waves is similar to imaging using X-rays, but unlike X-rays it is not a form of ionizing radiation.
He adds that this can be generated using specific terahertz devices, such as diodes or lasers. However, for spectroscopy applications,
"such as analyzing food for poisons or baggage for drugs or explosives it is useful for the terahertz radiation to be as'broadband'as possible,"
Buccheri explains that spectroscopy works by looking at which frequencies are absorbed by certain materials. Different materials have different spectra--they have peaks and troughs at different frequencies.
"Spectroscopy is like taking a picture, "said Buccheri.""If the camera has a low resolution,
"Until now, approaches to use a plasma as a broadband source of terahertz have used commonly an elongated plasma generated by combining together two laser beams of different frequencies, i e.,
requires powerful, expensive lasers. The"one-color"approach uses single laser frequency to generate the plasma.
Pioneered by Harald Hamster and colleagues in 1993, it required even higher laser energies and therefore it was explored not further until this recent paper by Buccheri and Zhang.
Buccheri explains that he has always been interested in the polarization of light and how it can be exploited for different uses.
He was interested in certain polarization states that exist for a beam of light: azimuthal or radial polarization.
In these states, the electric field is either perpendicular to the radial axis or radial at each given point."
if by creating a plasma with a laser in one of these"weirder"polarization states
"He adds that he was then able to exploit the physics to use lower laser energies than previously thought possible to generate broadband terahertz waves in air.
He thinks that fine tuning the type of laser used and changing the air to a different gas could enable even lower operation powers.
An advantage of this"one-color"approach to generating terahertz radiation is the fact that the terahertz waves propagate in a different direction to the laser beam.
#Scientists develop first liquid nanolaser To understand the concept, imagine a laser pointer whose color can be changed simply by changing the liquid inside it,
instead of needing a different laser pointer for every desired Color in addition to changing color in real time, the liquid nanolaser has additional advantages over other nanolasers:
it is simple to make, inexpensive to produce and operates at room temperature. Nanoscopic lasers--first demonstrated in 2009--are only found in research labs today.
They are, however, of great interest for advances in technology and for military applications.""Our study allows us to think about new laser designs
and what could be possible if they could actually be made, "said Teri W. Odom, who led the research."
"My lab likes to go after new materials, new structures and new ways of putting them together to achieve things not yet imagined.
We believe this work represents a conceptual and practical engineering advance for on-demand, reversible control of light from nanoscopic sources."
The liquid nanolaser in this study is not a laser pointer but a laser device on a chip,
The laser's color can be changed in real time when the liquid dye in the microfluidic channel above the laser's cavity is changed.
The laser's cavity is made up of an array of reflective gold nanoparticles, where the light is concentrated around each nanoparticle
and then amplified. In contrast to conventional laser cavities, no mirrors are required for the light to bounce back and forth.
Notably, as the laser color is tuned, the nanoparticle cavity stays fixed and does not change;
only the liquid gain around the nanoparticles changes. The main advantages of very small lasers are:
Some technical backgroundplasmon lasers are promising nanoscale coherent sources of optical fields because they support ultra-small sizes and show ultra-fast dynamics.
Although plasmon lasers have been demonstrated at different spectral ranges, from the ultraviolet to near-infrared, a systematic approach to manipulate the lasing emission wavelength in real time has not been possible.
The main limitation is that only solid gain materials have been used in previous work on plasmon nanolasers;
hence, fixed wavelengths were shown because solid materials cannot easily be modified. Odom's research team has found a way to integrate liquid gain materials with gold nanoparticle arrays to achieve nanoscale plasmon lasing that can be tuned dynamical, reversibly and in real time.
The use of liquid gain materials has two significant benefits: These nanoscale lasers can be mass-produced with emission wavelengths over the entire gain bandwidth of the dye.
Thus, the same fixed nanocavity structure (the same gold nanoparticle array) can exhibit lasing wavelengths that can be tuned over 50 nanometers, from 860 to 910 nanometers,
simply by changing the solvent the dye is dissolved in n
#Scientists create cheaper magnetic material for cars, wind turbines Karl A. Gschneidner and fellow scientists at the U s. Department of energy's Ames Laboratory have created a new magnetic alloy that is an alternative to traditional rare-earth permanent magnets.
The new alloy--a potential replacement for high-performance permanent magnets found in automobile engines and wind turbines--eliminates the use of one of the scarcest and costliest rare earth elements, dysprosium,
and instead uses cerium, the most abundant rare earth. The result, an alloy of neodymium, iron and boron co-doped with cerium and cobalt
"This is very different to an optical microscope, where light limits the size you can measure. This so-called'diffraction limit'plays no part in this new technology."
"A common way to decipher molecular structures is to use x-ray crystallography. This complicated method involves purifying and crystallising the molecules,
then firing x-rays through the sample and interpreting the resulting patterns. However, this is also problematic
In our everyday lives, the effects of the radiation pressure of light can be neglected. Your furniture is moved not over even though the light,
or more generally the electromagnetic radiation, emitted by your lamps bounces off from its surfaces thus creating a radiation pressure force.
An ordinary 100 Watt light-bulb causes a radiation pressure that is only a trillionth (one part to 1000000000000) of the normal atmospheric pressure.
In the recent years, the radiation pressure has been harnessed also in the field of laser physics. It can be used to couple the electromagnetic laser field to, for example,
the movement of the small mechanical oscillators that can be found inside ordinary watches. Due to the weakness of the interaction, one typically needs substantially strong laser fields."
"Radiation pressure physics in these systems have become measurable only when the oscillator is hit by millions of photons,
"Like a light switch, one-shot learning is either on, or it's off, "says Shimojo. In the behavioral study, 47 participants completed a simple causal-inference task;
and a laser diode, all enclosed in a small, 3d printed case and integrated to act just like a fluorescence microscope.
The group discovered a few wavelengths of light that allow measuring the specific fluorescence signal from photosynthesis. The team's fluorescence measurement system can record radiation at high resolution with a frequency of 5 minutes,
In light of our results, these rules need to be reviewed to take into account the possibility of airborne transmission of noroviruses.
and employing standard photolithography. This effectively proved that these three-atom-thick semiconducting films can be made into multilevel electronic devices of unsurpassed thinness.
#Compact light source improves CT SCANS With its ability to image cross sections of the human body, X-ray computer tomography (CT) has become an important diagnostic tool in medicine.
"Our work demonstrates that we can achieve better results with the Compact Light source, "says Professor for Biomedical Physics Franz Pfeiffer of the Technical University of Munich in Germany, who led the new study published April 20 in the Proceedings of the National Academy of Sciences."
these methods require X-ray light with a well-defined wavelength aligned in a particular way--properties that conventional CT SCANNERS in hospitals do not deliver sufficiently.
Conversely, the CLS is a miniature version of a synchrotron that produces suitable X-rays by colliding laser light with electrons circulating in a desk-sized storage ring.
A new study demonstrates for the first time that an antimicrobial dye activated by light avidly adheres to bone to prevent bacteria from growing on bone fragments used in reconstructive surgery
and appear to have excellent antimicrobial properties in the presence of light, "says Noreen Hickok, Ph d.,Associate professor of Orthopedic Surgery at Thomas Jefferson University."
which occur in bright light.""Surgeons often use bone chips or bone powder as a sort of putty during bone reconstruction to help areas of bone re-grow.
But when the lights go on, TAPP becomes active, producing chemicals called reactive oxygen species, or ROS, that rapidly kill the bacteria.
As long as the lights were on, bacteria was unable to attach and grow on the surface of the bone.
and the other would be the continuation of the activation in the bright lights of the surgical suite
The direction of the spin can be detected with the aid of fluorescence spectroscopy. Extremely fast spin oscillation In this latest publication, the scientists have shaken the resonators in a way that allows them to induce a coherent oscillation of the coupled spin for the first time.
It uses a method known as ultrafast electron diffraction (UED) and can reveal motions of electrons
The technique complements ultrafast studies with SLAC's X-ray free-electron laser. Similar to X-ray light, highly energetic electrons can take snapshots of the interior of materials as they pass through them.
Yet electrons interact differently with materials and"see"different things. Both methods combined draw a more complete picture that will help researchers better understand
The superior performance of the new UED system is due to a very stable"electron gun"originally developed for SLAC's X-ray laser Linac Coherent light Source (LCLS), a DOE Office of Science User Facility.
The scattered waves then combine to form a so-called diffraction pattern picked up by a detector.
The whole apparatus works like a high-speed camera, capturing differences in diffraction patterns over time that scientists use to reconstruct the sample's inner structure and how it changes.
for instance in response to ultrashort laser pulses.""UED has been under development for the past 10 to 15 years,
"LCLS expertise in electron gun technology and ultrafast laser systems gives our system the performance and stability needed to study much faster processes."
"Due to the almost 1, 000-fold shorter wavelength of electrons compared to X-rays, UED can see much finer structural details.
The scientists'ultimate goal is to turn UED into an ultrafast electron microscope--an instrument that would show details too small to be seen with an optical microscope.
when laser science and X-ray science merged into the new field of ultrafast X-ray science."
#New 2d transistor material made using precision lasers Last year a multi-discipline research team led by South korea's Institute for Basic Science (IBS) Center for Integrated Nanostructure Physics
They directed a 1 m wide laser (a human hair is 17 to 181 m) at the 2h-Mote2
developing a new method to extract more efficient and polarized light from quantum dots (QDS) over a large-scale area.
and photonic crystal technology, could lead to brighter and more efficient mobile phone, tablet, and computer displays, as well as enhanced LED lighting.
They then used electrohydrodynamic jet (e-jet) printing technology to precisely print the QD-embedded polymers onto photonic crystal structures.
These photonic crystals limit the direction that the QD-generated light is emitted meaning they produce polarized light,
their replica molded photonic crystals could someday lead to brighter, less expensive, and more efficient displays."
"If you start with polarized light, then you double your optical efficiency, "See explained.""If you put the photonic crystal-enhanced quantum dot into a device like a phone or computer,
then the battery will last much longer because the display would only draw half as much power as conventional displays."
See fabricated a novel 1mm device (aka Robot Man) made of yellow photonic crystal-enhanced QDS.
Raman spectroscopy and transport measurements on the graphene/boron nitride heterostructures reveals high electron mobilities comparable with those observed in similar assemblies based on exfoliated graphene.
the inability to work in bright light, especially sunlight. The key is to gather only the bits of light the camera actually needs.
so that the camera and its light source work together efficiently, eliminating extraneous light, or"noise,"that would
otherwise wash out the signals needed to detect a scene's contours.""We have a way of choosing the light rays we want to capture
"One prototype based on this model synchronizes a laser projector with a common rolling-shutter camera-the type of camera used in most smartphones
-so that the camera detects light only from points being illuminated by the laser as it scans across the scene.
This not only makes it possible for the camera to work under extremely bright light or amidst highly reflected
when the camera captures ambient light from a scene. But as a projector scans a laser across the scene,
the spots illuminated by the laser beam are brighter, if only briefly, noted Kyros Kutulakos, U of T professor of computer science."
"Even though we're not sending a huge amount of photons, at short time scales, we're sending a lot more energy to that spot than the energy sent by the sun,
The trick is to be able to record only the light from that spot as it is illuminated,
this is accomplished by synchronizing the projector so that as the laser scans a particular plane, the camera accepts light only from that plane.
despite the light scattering that usually makes it impenetrable to cameras. Manufacturers also could use the system to look for anomalies in shiny or mirrored components.
The team's concept then adds Raman spectroscopy to its centrifugal microfluidic platform.""Raman spectroscopy uses the way light interacts with matter to produce'unique scattering,'the equivalent of a molecular fingerprint,
which can then be used to identify the types of bacteria present, "said Ute Neugebauer, group leader at the Jena University Hospital and Leibniz Institute of technology.
The team will continue toward its goal of developing an easy-to-use spectroscopy-based point-of-care medical device for fast and reliable diagnostics."
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