and transport fundamental particles of light called photons. The tiny device is just. 7 micrometers by 50 micrometer (about. 00007 by. 005 centimeters) and works almost like a seesaw.
On each side of the seesaw benches researchers etched an array of holes called photonic crystal cavities.
Even though the particles of light have no mass the captured photons were able to play seesaw
so that the quantum physics of light can be revealed and harnessed. The ability to mechanically control photon movement as opposed to controlling them with expensive and cumbersome optoelectronic devices could represent a significant advance in technology said Huan Li the lead author of the paper.
They expect that such devices could play a role in developing microelectronic circuits that would use light instead of electrons to carry data
Breakthrough in light sources for new quantum technology More information: Optomechanical photon shuttling between photonic cavities Nature Nanotechnology (2014) DOI:
#A nanosized hydrogen generator (Phys. org) esearchers at the US Department of energy's (DOE) Argonne National Laboratory have created a small scale"hydrogen generator"that uses light
"For Rozhkova, this particular building block is inspired by the function of an ancient protein known to turn light into energy.
and platinum and then exposing them to ultraviolet light. There is just one downside: titanium dioxide only reacts in the presence of ultraviolet light,
which makes up a mere four percent of the total solar spectrum. If the researchers wanted to power their generators with sunlight,
In order to produce greater amounts of hydrogen using visible light, the researchers looked for a new material.
Graphene is a super strong, super light, near totally transparent sheet of carbon atoms and one of the best conductors of electricity ever discovered.
both the br protein and the graphene platform absorb visible light. Electrons from this reaction are transmitted to the titanium dioxide on
making the titanium dioxide sensitive to visible light. Simultaneously, light from the green end of the solar spectrum triggers the br protein to begin pumping protons along its membrane.
and time-resolved spectroscopy at the Center for Nanoscale Materials verified the movements of the electrons within the system,
In their study the researchers used x-ray photoelectron spectroscopy and Raman spectroscopy to confirm that the bioreceptor molecules had attached to the graphene biosensor once fabricated
In 2012, they demonstrated a tunable device that can absorb 99.75%of infrared light, appearing black to infrared cameras.
which electromagnetic radiation interacts with your material, "says Jian Shi, lead author of the paper in Nature Communications.
you're dynamically controlling how light interacts with this material.""Further ahead, Researchers at the Center for Integrated Quantum Materials, established at Harvard in 2013 through a grant from the National Science Foundation,
Scanning tunneling microscopy/spectroscopy of picene thin films formed on Ag (111) by Yasuo Yoshida Hung-Hsiang Yang Hsu-Sheng Huang Shu-You Guan Susumu Yanagisawa Takuya
#Study sheds new light on why batteries go bad A comprehensive look at how tiny particles in a lithium ion battery electrode behave shows that rapid-charging the battery
and took them to Berkeley Lab for examination with intense X-rays from the Advanced Light source synchrotron a DOE Office of Science User Facility.
"The researchers use a direct laser writing method called two-photon lithography to"write"a three-dimensional pattern in a polymer by allowing a laser beam to crosslink
The parts of the polymer that were exposed to the laser remain intact while the rest is dissolved away, revealing a three-dimensional scaffold.
and light that can be captured by a high-quality digital camera. The film, just one-60th the thickness of a human hair, is a sort of"electronic skin"able to sense texture and relative stiffness.
Ruffieux and his team have noticed that particularly narrow graphene nanoribbons absorb visible light exceptionally well and are therefore highly suitable for use as the absorber layer in organic solar cells.
which absorbs light equally at all wavelengths the light absorption in graphene nanoribbons can be increased enormously in a controlled way
#Ultra-thin high-speed detector captures unprecedented range of light waves New research at the University of Maryland could lead to a generation of light detectors that can see below the surface of bodies walls and other objects.
Using the special properties of graphene a two-dimensional form of carbon that is only one atom thick a prototype detector is able to see an extraordinarily broad band of wavelengths.
Included in this range is a band of light wavelengths that have exciting potential applications but are notoriously difficult to detect:
The light we see illuminating everyday objects is actually only a very narrow band of wavelengths and frequencies.
Terahertz light waves'long wavelengths and low frequencies fall between microwaves and infrared waves. The light in these terahertz wavelengths can pass through materials that we normally think of as opaque such as skin plastics clothing and cardboard.
It can also be used to identify chemical signatures that are emitted only in the terahertz range.
because when light is absorbed by the electrons suspended in the honeycomb lattice of the graphene they do not lose their heat to the lattice
New'T-ray'tech converts light to sound for weapons detection medical imaging More information: Sensitive Room-temperature Terahertz Detection via Photothermoelectric Effect in Graphene Xinghan Cai et al.
and organic light emitting diodes (OLED) technology to achieve full colour and video functionality. Lightweight flexible active-matrix backplanes may also be used for sensors
and light along the same tiny wire a finding that could be a step towards building computer chips capable of transporting digital information at the speed of light.
Using a laser to excite electromagnetic waves called plasmons at the surface of the wire the researchers found that the Mos2 flake at the far end of the wire generated strong light emission.
which emitted light of the same wavelength. We have found that there is pronounced nanoscale light-matter interaction between plasmons
because devices that focus light cannot be miniaturized nearly as well as electronic circuits said Goodfellow. The new results hold promise for guiding the transmission of light
Combining electronics and photonics on the same integrated circuits could drastically improve the performance and efficiency of mobile technology.
The researchers say the next step is to demonstrate their primitive circuit with light emitting diodes.
K. Goodfellow R. Beams C. Chakraborty L. Novotny A n. Vamivakas Integrated nanophotonics based on nanowire plasmons and atomically-thin material Optica Vol. 1 Issue
(impedance spectroscopy) that is affordable, widely available to manufacturers, and relatively easy to perform. The technique is repeatable, non-destructive,
when exposed to light, and that technology has enabled a fast-growing industry. The most familiar designs use rigid layers of silicon crystal.
acts as a large solar system that can be used to recharge portable electronics and lights for the upcoming night of camping."
"A lot of the understanding being developed here can also be applied to make better organic light emitting diodes, "Richter explains.
For the impedance spectroscopy measurements, the sample was installed beneath an LED broadband white light, calibrated to one Sun illumination (natural sunlight).
"We can also do these same measurements absent the light source along the same voltage range,
2 In LPTP, the organic photovoltaic sample is illuminated with a laser pulse, which results in a temporary high-voltage that decays over a time from nanosecond to seconds.
These resulting data provide additional information about the recombination effects in the device that impedance spectroscopy is unable to provide.
because they can see far smaller structures than regular light or X-ray microscopes. They use electrons
which are hundreds of times smaller than the wavelengths of light to map the landscape all the way down to molecules and even atoms.
The researchers used a handheld device resembling a laser pointer that can detect Raman nanoprobes with very high accuracy.
We show that SERS image-guided resection is more accurate than resection using white light visualization alone.
#Ultrafast graphene based photodetectors with data rates up to 50 GBIT/s In cooperation with Alcatel Lucent Bell labs researcher from AMO realized the worldwide fastest Graphene based photodetectors.
In the current work Graphene based photodetectors were integrated in a conventional silicon photonic platform designed for future on-chip applications in the area of ultrafast data communication.
In addition the specific features of Graphene-based photodetectors like dark current free and high speed operation
not only set a new benchmark for graphene based photodetectors but also demonstrate for the first time that Graphene based photodetectors surpass comparable detectors based on conventional materials concerning maximal data rates.
The work was supported by the European commission through the Flagship project Graphene and the integrated project Grafol as well as the DPG supported project Gratis.
The publication is published in the international renowned journal ACS Photonics and was chosen as Editor's Choice article.
50 GBIT/s photodetectors based on wafer-scale graphene for integrated silicon photonic communication systems. ACS Photonics Just Accepted Manuscript.
DOI: 10.1021/ph500160 6
#Graphene reinvents the future For many scientists the discovery of one-atom-thick sheets of graphene is hugely significant something with the potential to affect just about every aspect of human activity and endeavour.
"Our experimental demonstration of such junctions between two-dimensional materials should enable new kinds of transistors, LEDS, nanolasers,
"The researchers have demonstrated already that the junction interacts with light much more strongly than the rest of the monolayer,
The separation of photoexcited electrons and holes is essential for driving an electrical current in a photodetector or solar cell."
not only for photonics and optoelectronics, but also for photovoltaics.""MX2 semiconductors have extremely strong optical absorption properties
#Biomimetic photodetector'sees'in color (Phys. org) Rice university researchers have created a CMOS-compatible biomimetic color photodetector that directly responds to red green
and blue light in much the same way the human eye does. The new device was created by researchers at Rice's Laboratory for Nanophotonics (LANP)
and is described online in a new study in the journal Advanced Materials. It uses an aluminum grating that can be added to silicon photodetectors with the silicon microchip industry's mainstay technology complementary metal-oxide semiconductor or CMOS.
Conventional photodetectors convert light into electrical signals but have no inherent color-sensitivity. To capture color images photodetector makers must add color filters that can separate a scene into red green and blue color components.
This color filtering is done commonly using off-chip dielectric or dye color filters which degrade under exposure to sunlight
and can also be difficult to align with imaging sensors. Today's color filtering mechanisms often involve materials that are not CMOS-compatible
The color photodetector resulted from a $6 million research program funded by the Office of Naval Research that aimed to mimic cephalopod skin using metamaterials compounds that blur the line between material and machine.
Based on that hypothesis LANP graduate student Bob Zheng the lead author of the new Advanced Materials study set out to design a photonic system that could detect colored light.
Zheng's color photodetector uses a combination of band engineering and plasmonic gratings comb-like aluminum structures with rows of parallel slits.
which is a common technique in CMOS processing Zheng deposited a thin layer of aluminum onto a silicon photodetector topped with an ultrathin oxide coating.
Color selection is performed by utilizing interference effects between the plasmonic grating and the photodetector's surface.
and the width and spacing of the slits Zheng was able to preferentially direct different colors into the silicon photodetector
Light of a specific wavelength can excite a plasmon and LANP researchers often create devices where plasmons interact sometimes with dramatic effects.
You get this funneling of light into a concentrated area. Not only are we using the photodetector as an amplifier we're also using the plasmonic color filter as a way to increase the amount of light that goes into the detector he said.
Explore further: Researchers use aluminum nanostructures for photorealistic printing of plasmonic color palettes More information:
modern materials that are light, flexible and highly conductive have extraordinary technological potential, whether as artificial skin or electronic paper.
#Color hologram uses plasmonic nanoparticles to store large amounts of information In the 4th century, the Romans built a special glass cup,
which way the light is shining through it. The glass is made of finely ground silver
at the University of Cambridge in the UK, have used surface plasmon resonance as a new way to construct holograms.
Similar to the Lycurgus cup, the new holograms can change colors due to light scattering off silver nanoparticles of specific sizes and shapes.
the new holograms could have applications in 3d displays and information storage devices, among others.""This experiment is inspired by the very unique optical properties shown by the Lycurgus cup,
"This exceptional piece changes in color according to the position of the light source. If illuminated from one side it looks green,
"Although there are several different ways to construct holograms, almost all traditional holograms are single-color,
and the multicolor holograms that do exist face limitations. For instance, no methodology exists that can produce multicolor holograms from a surface.
Here, the researchers demonstrated that it is possible to construct multicolor holograms from a single plane.
The new holograms consist of precisely engineered silver nanoparticles patterned over a substrate. A key difference in the new holograms is the smaller size of the diffraction fringes,
which control the light wavelength interference. In traditional holograms, these fringes are larger than half the wavelength of light.
In contrast the fringes here are replaced with nanoparticles smaller than half the wavelength of light.
The researchers showed that the narrower band diffraction, which creates the colorful effects, is produced by plasmonic-enhanced optical scattering of the nanostructures.
The subwavelength distance offers certain advantages. For instance, two different types of plasmonic nanoparticles can be multiplexed, or combined but not coupled, at subwavelength distances.
By using nanoparticles of silver with different shapes and sizes, the researchers could control the colors.
In addition to providing multiple colors, multiplexing two nanoparticles has the advantage of increasing the bandwidth information limits.
The researchers showed that each nanoparticle carries independent information such as polarization and wavelength, which can be controlled simultaneously.
With twice the number of nanoparticles, the total amount of binary information stored can exceed the traditional limits of diffraction."
"It has been shown that nanoparticles with resonant properties can be uncoupled over subwavelength distances so their electromagnetic fields have minimal interaction,
and transfer independent information beyond the diffraction limits, which is in contrast to nonresonant structures.
Because of the nature of this phenomenon, it has been possible to demonstrate, for the first time, a hologram that projects color images in 180 degrees.
"These features make the new hologram very attractive for future applications.""Besides the evident application in replacing the typical'rainbow holograms'of credit cards and other security items,
this phenomenon can be used for image projection on spheres, which so far has not been achieved with conventional optics,
"The main goal is the integration of new modulation schemes to produce ultra-thin displays and dynamic holograms
A new method which uses tightly confined light trapped between gold mirrors a billionth of a metre apart to watch molecules'dancing'in real time could help researchers uncover many of the cell processes that are essential to all life
Researchers from the University of Cambridge have demonstrated how to use light to view individual molecules bending
Through highly precise control of the geometry of the nanostructures and using Raman spectroscopy an ultra-sensitive molecular identification technique the light can be trapped between the mirrors allowing the researchers to'fingerprint'individual molecules.
It's like having an extremely powerful magnifying glass made out of gold said Professor Jeremy Baumberg of the Nanophotonics Centre at Cambridge's Cavendish Laboratory who led the research.
Analysing the colours of the light which is scattered by the mirrors allowed the different vibrations of each molecule to be seen within this intense optical field.
Probing such delicate biological samples with light allows us to watch these dancing molecules for hours without changing
By continuously observing the scattered light individual molecules are seen moving in and out of the tiny gaps between the mirrors.
first light needs a good conductor in order to get converted into usable energy; secondly the cell also has to be transparent for light to get through.
Most solar cells on the market use indium tin oxide with a nonconductive glass protective layer to meet their needs.
and SGM beamlines at the Canadian Light source as well as a Beamline 8. 0. 1 at the Advanced Light source Hunt set out to learn more about how oxide groups attached to the graphene lattice changed it
"We had already been able to show that tungsten diselenide can be used to turn light into electric energy
letting most of the light in, but still creating electricity. As it only consists of a few atomic layers,
it is extremely light weight (300 square meters weigh only one gram), and very flexible. Now the team is working on stacking more than two layers this will reduce transparency
the team used an advanced version of a polarised light microscope based at the Marine Biological Laboratory, USA,
the Brookhaven team used a combination of full-field, nanoscale-resolution transmission x-ray microscopy (TXM) and x-ray absorption near-edge spectroscopy (XANES) at the National Synchrotron Light source (NSLS),
Raman spectroscopy allows researchers to measure these bonds and vibrations. Housed within the Center for Nanoscale Materials a DOE Office of Science User Facility the spectroscope allows researchers to use light to shift the position of one atom in a crystal lattice
which in turn causes a shift in the position of its neighbors. Scientists define a material by measuring how strong
and characterize inkjet printed 2d crystal-based flexible photodetectors and study their integration with commercial electronics.
Photodetectors are needed in cameras automotive applications sensing and telecommunications medical devices and security he says. If these could be made flexible they could be integrated in clothes rolled up
This represents a strong limitation for flexible electronics in a wide range of applications from active matrix displays to ultrafast light detectors and gas sensors.
and insulating properties with a faster response time outperforming the current organic semiconducting inks enabling printed flexible photodetectors
When light impinges on a semiconducting 2d crystal (e g. Mos2) due to their 2d nature electrons and holes are generated with a higher efficiency than the current photodetectors based on siliconthe project funded by the National Natural science Foundation of China looks into how to design printed flexible photodetectors
based on graphene and 2d crystal-inks. The optical response of the printed 2d crystal inks combined with their flexibility on plastic substrate
#Tiny laser sensor heightens bomb detection sensitivity New technology under development at the University of California,
UC Berkeley professor of mechanical engineering, has found a way to dramatically increase the sensitivity of a light-based plasmon sensor to detect incredibly minute concentrations of explosives.
The device works by detecting the increased intensity in the light signal that occurs as a result of this interaction.
Because of this, the researchers are hopeful that their plasmon laser sensor could detect pentaerythritol tetranitrate, or PETN, an explosive compound considered a favorite of terrorists.
The ability to increase the sensitivity of optical sensors had traditionally been restricted by the diffraction limit,
a limitation in fundamental physics that forces a tradeoff between how long and how small light can be trapped.
researchers were able to squeeze light into nanosized spaces, but sustaining the confined energy was challenging
The new device builds upon earlier work in plasmon lasers by Zhang's lab that compensated for this light leakage by using reflectors to bounce the surface plasmons back and forth inside the sensor similar to the way sound waves are reflected across the room
which work by detecting shifts in the wavelength of light.""The difference in intensity is similar to going from a light bulb for a table lamp to a laser pointer,
"he said.""We create a sharper signal which makes it easier to detect even smaller changes for tiny traces of explosives in the air
so they can use the devices in bright light. One of the most promising developments involves layering anti-reflective nanostructures on top of an anti-glare surface.
#Nanophotonics experts create powerful molecular sensor Nanophotonics experts at Rice university have created a unique sensor that amplifies the optical signature of molecules by about 100 billion times.
which is described this week in the journal Nature Communications, uses a form of Raman spectroscopy in combination with an intricate but mass reproducible optical amplifier.
Researchers at Rice's Laboratory for Nanophotonics (LANP) said the single-molecule sensor is about 10 times more powerful that previously reported devices."
"The optical sensor uses Raman spectroscopy, a technique pioneered in the 1930s that blossomed after the advent of lasers in the 1960s.
By measuring and analyzing these re-emitted photons through Raman spectroscopy, scientists can decipher the types of atoms in a molecule as well as their structural arrangement.
a two-coherent-laser technique called"coherent anti-Stokes Raman spectroscopy,"or CARS. By using CARS in conjunction with a light amplifier made of four tiny gold nanodiscs,
"The two-coherent-laser setup in SECARS is important because the second laser provides further amplification,
"Zhang said.""In a conventional single-laser setup, photons go through two steps of absorption and re-emission,
and the optical signatures are amplified usually around 100 million to 10 billion times. By adding a second laser that is coherent with the first one,
the SECARS technique employs a more complex multiphoton process.""Zhang said the additional amplification gives SECARS the potential to address most unknown samples.
That's an added advantage over current techniques for single-molecule sensing, which generally require a prior knowledge about a molecule's resonant frequency before it can be measured accurately.
Another key component of the SECARS process is the device's optical amplifier, which contains four tiny gold discs in a precise diamond-shaped arrangement.
"the optical signatures of molecules caught in that gap are amplified dramatically because of the efficient light harvesting and signal scattering properties of the four-disc structure.
Recently, there has been a lot of interest in fabricating metal-based nanotextured surfaces that are preprogrammed to alter the properties of light in a specific way after incoming light interacts with it,
what is currently achievable using conventional electron-beam lithography techniques).""On a fundamental level, our work demonstrates electron-beam based manipulation of nanoparticles an order of magnitude larger than previously possible,
what is currently achievable using conventional electron-beam lithography techniques). The team demonstrated that an electron beam from a standard scanning electron microscope (SEM) can be used to deform either individual p-BNA structures
A photonic crystal fiber was used to generate (quasi-white light) supercontinuum to probe the spectral response of select regions within the array.
which avoids complications such as proximity effects from conventional lithography techniques, "Bhuiya said.""This process also reduces the gap of the nanoantennas down to 5 nm under SEM with a controlled reduction rate.
which emits ions instead of light at superior resolution. Like the needle of a record player, the microscopes can trace out the topography of silicon atoms, sensing surface features on the atomic scale.
By shining light onto such a nanoantenna, the electrons inside start moving back and forth, amplifying the light radiation in hot spots regions of the antenna,
also amplify the light in an area close to that surface. In biosensors, protein molecules are identified by irradiating them with infrared light
and by analysing the spectrum of the light they emit, known as a Raman spectrum. If these molecules are close to nanoparticles,
the plasmons in the nanoparticles enhance the Raman signal coming from the molecules that have to be detected with several orders of magnitude.
When, subsequently, these nanoantennas are illuminated with light, they show the Raman fingerprints of both the bioreceptor and the biomarker,
The high surface area and confined nature of nanowires allows them to trap significant amounts of light for solar cell operations.
Nanoholes are particularly effective at capturing light because photons can ricochet many times inside these openings until absorption occurs.
Instead of traditional time-consuming lithography, the researchers identified a rapid, 'maskless'approach to producing nanoholes using silver nanoparticles.
which they toughened by annealing it using a rapid-burst ultraviolet laser. Careful optimization of this procedure yielded regular arrays of silver nanospheres on top of the silicon surface,
with sphere size and distribution controlled by the laser annealing conditions. Next, the nanosphereilicon complex was immersed into a solution of hydrogen peroxide and hydrofluoric acid mixture that eats away at silicon atoms directly underneath the catalytic silver nanospheres.
cavities deeper than one micrometer showed sharp drops in power conversion efficiency from a maximum of 8. 3 per cent due to light scattering off of rougher surfaces and higher series resistance effects."
which is spin-coated on the quarts substrates using PIM-1 solution with light green color
They also are exploring using lasers to precisely shrink the plastic in specific patterns. Nam first had the idea for using Shrinky Dinks plastic to assemble nanomaterials after seeing a microfluidics device that used channels made of shrinking plastic.
that could harvest energy from light much more efficiently than traditional thin-film solar cells s
able to transmit light and electricity with specific characteristics. This pressure-regulated fine-tuning of particle separation enables controlled investigation of distance-dependent optical and electrical phenomena.
This interaction enables the energy transfer between the internalized molecules says Raymo director of the UM laboratory for molecular photonics.
Subramani Swaminathan and Janet Cusido from the UM's Laboratory for Molecular Photonics Department of chemistry in the College of Arts and Sciences;
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