#New tiny silicon chip paves the way for light-speed computers The smallest ever'ultracompact polarisation beamsplitter'-a component used in silicon photonic chips-has been developed by engineers in the US,
and putting it in a new type of silicon photonic chip. That means no conversion process to slow everything down,
"With all light, computing can eventually be millions of times faster, "Menon said. Menon and his team figured out how to take current beamsplitters,
they were still able to perform their most important function-splitting guided light beams into the chip two components.
Melon and his team have paved the way for a single silicon photonic chip to be loaded with millions of them,
"The first supercomputers using silicon photonics-already under development at companies such as Intel and IBM-will use hybrid processors that remain partly electronic,
A team of European researchers has announced just that they've set a new record by creating black silicon solar cells that can convert 22.1 percent of the Sun's light into electricity-an increase of almost four percent on their previous record.
thanks to their ability to suck up light even when the Sun was low in the sky."
which helps them absorb the most visible and infrared light possible. Once this light is captured, a quantum reaction occurs that results in the production of electrons.
But because of all those nano-ridges, the electrons tend to recombine with the photovoltaic surface of the black silicon,
Publishing in Nature Nanotechnology, the researchers report that their resulting cells are the most efficient black silicon solar cells to date, capable of turning 22.1 percent of available light into electricity."
and could help electric cars travel further on a single charge, thanks to their light and bendy structure.
#Light-based computers will be even more awesome than we thought Researchers have come up with an efficient way of transporting data between computer chips using light rather than electricity.
theye struggled to find an efficient way to transmit that light across the thousands of different connections,
In theory, light can be beamed between chips via silicon structures that bend it to the desired location,
and have made several copies in their lab. Reporting in Nature Photonics, the team has demonstrated now that these devices worked perfectly,
Called'Light and Charge',these prototype street lights combine energy-efficient Light Emitting Diodes (LED) and BMW Chargenow recharging stations,
The team announced that it would be testing the Light and Charge system out in Munich, Germany next year,
and use a control panel on the light to swipe their charge card and register their use.
when the light is too low for the power cells. At $15, 000 per unit, the price tag might sound exorbitant,
Impressively, it also radiates heat out at specific infrared wavelengths that aren't absorbed by the atmosphere-allowing it to beam the heat directly into space."
#Researchers create holograms you can touch using high-powered lasers Three-dimensional, interactive holograms are now a reality,
thanks to researchers in Japan who have used powerful, ultra-quick lasers to produce holograms that can be physically felt
and respond to human touch. According to volunteers who have tested these interactive holograms, the mid-air mirages feel somewhere between sandpaper and a static shock.
They're made using tiny points of plasma light called voxels, that are created when the focused energy of a laser ionises the surrounding air.
The lasers used by the team from the University of Tsukuba's Digital Nature Group (DNG) are special femtosecond lasers transmitting in bursts of 30 to 270 femtoseconds (1 femtosecond is a quadrillionth of a second
Combined with a spatial light modulator, a mirror, and a Galvano scanner (used to precisely target lasers),
the DNG team was able to create shapes up to 1 cm cubed with a resolution of up to 200,000 dots-per-second at the highest setting.
That high speed means the holograms can respond in real-time to touches and add a level of interactivity with the help of a camera underneath,
The key to preventing the lasers from burning skin was reducing the duration of the laser's bursts-the sweet spot was between 50 milliseconds and 1 second.
Team leader Yoichi Ochiai says the hologram size is limited by the size of the spatial light modulator included in the setup,
but the potential is there once scientists work out how to make these holograms larger and more varied."
"The spatial light modulator can modify the phases of light rates and produce various spatial distributions of light based on interference,"explains the team from DNG."
"Our results led to calmer and safer plasma generation that can be incorporated into our daily lives."
the technique also uses Extreme Ultraviolet (EUV) lithography to etch the microscopic patterns required into each chip.
whereas LHCB conducted the search with the lights on, and from all angles,"the CERN release explains.
A sophisticated laser system sends laser beams into different directions. Therefore different pictures are visible from different angles.
In 2013 the young start-up company Trilite Technologies had the idea to develop this new kind of display which sends beams of light directly to the viewers'eyes.
But the crucial point is that the individual laser pixels work. Scaling it up to a display with many pixels is not a problem says Jrg Reitterer (Trilite Technologies and Phd-student in the team of Professor Ulrich Schmid at the Vienna University of Technology.
Every single 3d-Pixel (also called Trixel) consists of lasers and a moveable mirror. The mirror directs the laser beams across the field of vision from left to right.
During that movement the laser intensity is modulated so that different laser flashes are sent into different directions says Ulrich Schmid.
To experience the 3d effect the viewer must be positioned in a certain distance range from the screen.
If the distance is too large both eyes receive the same image and only a normal 2d picture can be seen.
#Laser-induced graphene'super'for electronics: Flexible 3-D supercapacitors tested Rice university scientists advanced their recent development of laser-induced graphene (LIG) by producing
and testing stacked, three-dimensional supercapacitors, energy storage devices that are important for portable, flexible electronics. The Rice lab of chemist James Tour discovered last year that firing a laser at an inexpensive polymer burned off other elements and left a film of porous graphene, the much-studied atom-thick
lattice of carbon. The researchers viewed the porous, conductive material as a perfect electrode for supercapacitors or electronic circuits.
An electron microscope image shows the cross section of laser-induced graphene burned into both sides of a polyimide substrate.
since their work to make vertically aligned supercapacitors with laser-induced graphene on both sides of a polymer sheet.
It's done on a commercial laser system, as found in routine machine shops, in the open air."
and fabricated a waveplate that can transform the polarization state of light, "said Zhi Hao Jiang,
For instance, if we transform linearly polarized light into circularly polarized light, this could be useful in optical communication and biosensing."
and can achieve very wide broadband functionality in the visible to near infrared wavelength range.
Funded through a National Science Foundation Major Research Instrumentation grant, the new highly sensitive, laser-based instrument provides scientists with a method to more accurately measure global human exposure to mercury.
The measurement approach is called sequential two-photon laser induced fluorescence (2p-LIF) and uses two different laser beams to excite mercury atoms
and monitor blue shifted atomic fluorescence. UM Rosenstiel School Professor of Atmospheric Sciences Anthony Hynes and colleagues tested the new mobile instrument
titled"Deployment of a sequential two-photon laser-induced fluorescence sensor for the detection of gaseous elemental mercury at ambient levels:
You make both parts--the detectors and the photonic chip--through their best fabrication process which is dedicated
But any quantum computer--say one whose qubits are trapped laser ions or nitrogen atoms embedded in diamond--would still benefit from using entangled photons to move quantum information around.
So there's been an effort to miniaturize these optical circuits onto photonic integrated circuits. The project was a collaboration between Englund's group and the Quantum Nanostructures and Nanofabrication Group
Similar design strategies have great potential for use in a wide variety of human-made systems, from biomedical devices to microelectromechanical components, photonics and optoelectronics, metamaterials, electronics, energy storage
including the most advanced ones used in photonics and electronics. A stretched, soft substrate imparts forces at precisely defined locations across such a structure to initiate controlled buckling processes that induce rapid, large-area extension into the third dimension.
Compatibility with the most advanced materials (e g. monocrystalline inorganics), fabrication methods (e g. photolithography) and processing techniques (e g. etching, deposition) from the semiconductor and photonics industries suggest many possibilities for achieving sophisticated classes of 3d electronic
Quantum information promises unbreakable encryption because quantum particles such as photons of light can be created in a way that intrinsically links them.
Their solid-state technique is a promising alternative to using laser beams in optical fibres an approach which is used currently to create quantum networks around 100 kilometres long.
Even transporting our crystals at pedestrian speeds we have less loss than laser systems for a given distance.
We can now imagine storing entangled light in separate crystals and then transporting them to different parts of the network thousands of kilometres apart.
After writing a quantum state onto the nuclear spin of the europium using laser light the team subjected the crystal to a combination of a fixed and oscillating magnetic fields to preserve the fragile quantum information.
including time-lapse crystallography and single-crystal spectroscopy, to slow down the reaction rate by nearly 10,000 times.
The researchers used time-lapse crystallography and single-crystal spectroscopy to observe intermediate steps of the reaction."
and shaping of light beams A team of engineers has developed a new acousto-optic device that can shape
and steer beams of light at speeds never before achieved. The new technology will enable better optical devices to be made,
so does the shape of the light beam. Professor Drinkwater from the Department of Mechanical engineering said:"
This means that in the future laser beam-based devices will be able to be reconfigured much faster than is currently possible.
and a new generation of optical tweezers that will make them more rapidly reconfigurable and so allow better shaped traps to be produced.
Dr Mike Macdonald, Head of the Biophotonics research group at the University of Dundee, explained:"
"What we have shown can be thought of as a form of optical holography where the hologram can be made in real time using sound.
which has given us much greater flexibility in the control we have over light with these devices."
and will also allow for much higher laser powers to be used. This opens up applications such as beam shaping in laser processing of materials,
or even fast and high power control of light beams for free space optical communications using orbital angular momentum to increase signal bandwidth,
as shown recently by a demonstration in Vienna.""Professor Drinkwater added:""The number of applications of this new technology is vast.
"The capabilities of laser beam shaping and steering are crucial for many optical applications, such as optical manipulation and aberration correction in microscopy.
which are based on establishing a certain level of control over the phase of the laser beam.
and spatial light modulators (SLMS) are the common choice in a wide range of applications such as holography, optical tweezers and microscopy y
technique that focuses diffuse light inside a dynamic scattering medium containing living tissue. In addition they have improved the speed of optical focusing deep inside tissue by two orders of magnitude.
By detecting the wavefront of light emitted from the guide star they can determine an optimum phase pattern that allows scattered light moving along different paths to focus at the targeted location.
When light is shined into living biological tissue breathing and blood flow changes the optical interference or speckle pattern
Researchers use a type of mirror to record then time-reverse the ultrasound-modulated light emitted from the ultrasonic focus to achieve the best focus.
To overcome this obstacle the team used a fast-responding photorefractive crystal that is sensitive to light at the 790-nanometer wavelength making it suitable to focus light deep into biological tissue.
The new TRUE technology is able to focus light inside a dynamic medium with a speckle correlation time as short as 5. 6 milliseconds.
The improved speed allowed Wang to achieve the first optical focusing of diffuse light inside a scattering medium containing living biological tissue.
Going forward the team plans to implement the system in a reflection configuration where light is shined
The BSIT phenomenon permits light to travel in the forward direction while light traveling in the backward direction is absorbed strongly.
Light at certain wavelengths can be absorbed out of a thin optical waveguide by a microresonator
i e. we can make this system transparent again by adding another laser at a specially chosen wavelength nearby.
The effect occurs due to the interaction of the light with sound waves present in the material
but they are nonlinear devices requiring filtering of the scattered light. BSIT on the other hand is a linear nonreciprocal mechanism.
Physicists call this fast and slow light. Slow light techniques are extremely useful for quantum information storage and optical buffer applications.
Some day such buffers could be incorporated in quantum computers. While it is known already that the slow and fast light can be obtained using Brillouin scattering our device is far smaller
and uses far less power than any other previous demonstration by several orders-of-magnitude.
In their studies Bahl's research group uses the extremely minute forces exerted by light to generate
and transferring light signals to the brain for decoding. The causal mechanisms of this disease remain elusive.
However in light of time they decided to try regular Makerbot PLA Filament. The advantage of PLA is that it's used in all kinds of surgical implant devices says Dr. Smith.
which to convert light into power--more cost efficiently. The global PV market has experienced rapid growth in recent years due to renewable energy targets and CO2 EMISSION controls.
in converting light to power in a range of atmospheric conditions rather than just under direct sunlight.
The material was made in a single steel sheet using lasers to engrave"chiral, "or geometric microstructure patterns,
%among the highest reported in the field of perovskite-based light-to-energy conversion devices. The cells demonstrate little cell-to-cell variability,
which was developed by researchers from the University's Optoelectronics Research Centre (ORC) has potential applications in a number of fields that use pulsed lasers including telecommunications metrology sensing and material processing.
and manufacture a laser with these parameters exactly as required. Even when a suitable solution exists the size the complexity
and ease of operation of the laser are further critical considerations. The new method works on a fundamentally different principle to existing pulsed lasers.
It relies upon the coherent combination of multiple semiconductor lasers each operating continuous-wave at different precisely defined frequencies (wavelengths.
Through the precise control of the amplitude and phase of each laser's output it is possible to produce complex pulsed optical waveforms with a huge degree of user flexibility.
The key to making the approach work is to phase-lock the semiconductor lasers to an optical frequency comb
which ensures the individual lasers have well-defined mutual coherence. David Wu lead author of the study
and winner of the 2014 Engineering and Physical sciences Research Council (EPSRC) ICT Pioneers award for this work said:
First it is easily scalable--by combining a larger number of input lasers shorter or more complicated-shape pulses and/or more power can be obtained.
Finally it consists of miniature and low-cost semiconductor lasers that can be integrated all on the same chip making our pulse generator potentially very compact robust energetically efficient and low-cost.
We believe that this work is likely to be of direct interest to scientists working in virtually any field of optics where pulsed laser sources are used.
and phase-locking technology developed could be widely applicable with the broader optics/photonics community y
light sources; a pump; and a microfluidics chip with a fluorometer, also developed at the University Hospital Zurich.
If UV LIGHT is beamed onto these spiropyran molecules, they alter their chemical structure and become charged (polar).
When irradiated with visible light, they revert to their original, neutral structure. As a result, the membrane"opens
"if irradiated with UV LIGHT and glucose molecules diffuse relatively easily through the membrane from the skin.
If irradiated with visible light, considerably fewer glucose molecules pass through the membrane. The measurement involves sticking the measuring head,
to the baby's skin and irradiating it with visible light; some glucose molecules diffuse through the membrane from the skin.
The process is repeated then with UV LIGHT. The computer then uses these two different readings to calculate the premature baby's blood sugar level.
"For antireflection applications, the idea is to prevent light or radio waves from bouncing at interfaces between materials,"said physicist Charles Black,
and we'd like to capture the light irrespective of the direction it comes from. But each color of light couples best with a different antireflection coating,
The surfaces of their compound eyes have textured patterns made of many tiny"posts,"each smaller than the wavelengths of light.
The resulting surface nanotexture served to gradually change the refractive index to drastically cut down on reflection of many wavelengths of light simultaneously, regardless of the direction of light impinging on the solar cell."
As detailed in Rapid Communications in Mass Spectrometry, they validated the instrument--a laser ablation resonance ionization mass spectrometer--by dating a rock from Mars:
scientists have invented a new imaging system that causes tumors to ight upwhen a hand-held laser is directed at them. surgeon goal during cancer surgery is to remove the tumor,
A surgeon-controlled laser can be directed at any area of interest. In addition an imaging system with three cameras sits above the surgical field.
#Laser-generated surface structures create extremely water-repellent self-cleaning metals Super-hydrophobic materials are desirable for a number of applications such as rust prevention anti-icing or even in sanitation uses.
and his colleague at the University's Institute of Optics Anatoliy Vorobyev describe a powerful and precise laser-patterning technique that creates an intricate pattern of micro
This work builds on earlier research by the team in which they used a similar laser-patterning technique that turned metals black.
Guo adds that one of the big advantages of his team's process is that the structures created by our laser on the metals are intrinsically part of the material surface.
Unlike Guo's laser-treated metals the Teflon kitchen tools are not super-hydrophobic. The difference is that to make water to roll off a Teflon coated material you need to tilt the surface to nearly a 70-degree angle before the water begins to slide off.
but ultra-short laser pulses to change the surface of the metals. A femtosecond laser pulse lasts on the order of a quadrillionth of a second
but reaches a peak power equivalent to that of the entire power grid of North america during its short burst.
therefore make them very efficient at absorbing light. The combination of light-absorbing properties with making metals water repellent could lead to more efficient solar absorbers--solar absorbers that don't rust
and do need not much cleaning. Guo's team had blasted previously materials with the lasers and turned them hydrophilic meaning they attract water.
In fact the materials were so hydrophilic that putting them in contact with a drop of water made water run uphill.
Guo's team is now planning on focusing on increasing the speed of patterning the surfaces with the laser as well as studying how to expand this technique to other materials such as semiconductors
and has a lower output (100 W). An electronic control system manages the flow of energy between the solar panel the wind turbine the battery and the light.
#New laser for computer chips: International team of scientists constructs first germanium-tin semiconductor laser for silicon chips The transfer of data between multiple cores as well as between logic elements and memory cells is regarded as a bottleneck in the fast-developing computer technology.
Data transmission via light could be the answer to the call for a faster and more energy efficient data flow on computer chips as well as between different board components.
Signal transmission via copper wires limits the development of larger and faster computers due to the thermal load and the limited bandwidth of copper wires.
Through optical fibres signal propagation is almost lossless and possible across various wavelengths simultaneously: a speed advantage
However in spite of intensive research a laser source that is compatible with the manufacturing of chips is not yet achievable according to the head of Semiconductor Nanoelectronics (PGI-9). The basis of chip manufacturing is silicon an element of main group IV of the periodic table.
Typical semiconductor lasers for telecommunication systems made of gallium arsenide for example however are costly and consist of elements from main groups III
Such laser components cannot therefore be applied directly onto silicon. They have to be produced externally at great effort
Neither element is very efficient as a light source however. They are classed among the indirect semiconductors.
In contrast to direct semiconductors they emit mostly heat and only a little light when excited.
and thus make it a usable laser source. The scientists at Julich's Peter Grunberg Institute have succeeded now for the first time in creating a real direct main group IV semiconductor laser by combining germanium and tin
which is classed also in main group IV. The high tin content is decisive for the optical properties.
The functioning of the laser is limited so far to low temperatures of up to minus 183 degrees Celsius however.
Siegfried Mantl's group at PGI-9 Stephan Wirths applied the laser directly onto a silicon wafer
Phd student Richard Geiger fabricated the laser structures there. That way we were able to demonstrate that the germanium-tin compound can amplify optical signals as well as generate laser light reports Dr. Hans Sigg from the Laboratory for Micro and Nanotechnology.
The laser was excited optically for the demonstration. Currently the scientists in Dr. Dan Buca's group at Julich are working on linking optics and electronics even more closely.
The next big step forward will be generating laser light with electricity instead and without the need for cooling if possible.
The aim is to create an electrically pumped laser that functions at room temperature. The laser beam is not visible to the naked eye.
Gesn absorbs and emits light in a wavelength range of about 3 micrometres. Many carbon compounds such as greenhouse gases
or biomolecules also display strong absorption lines at this boundary between near and mid-wavelength infrared.
Hence sensors made of Gesn promise a new possibility of detecting these compounds. Along with computer chips completely new applications that have not been pursued so far for financial reasons may
thus benefit from the new laser material. Gas sensors or implantable chips for medical applications which can gather information about blood sugar levels
or other parameters via spectroscopic analysis are examples. In the future cost-effective portable sensor technology--which may be integrated into a smart phone--could supply real-time data on the distribution of substances in the air
#New high-speed 3-D microscope--SCAPE--gives deeper view of living things Her study is published in the Advance Online Publication (AOP) on Nature Photonics's website on January 19 2015.
While conventional light-sheet microscopes use two awkwardly positioned objective lenses Hillman realized that she could use a single-objective lens
A laser scanner in addition provides topographic measurements at millions of points. GFZ scientist Walter explains: This data allows us to quantify the erupted lava volumes
However this approach has a fundamental limit known as the diffraction limit which means that it can't be used to visualize objects much smaller than the wavelength of the light being used.
For example if you are using blue-green light with a wavelength of 500 nanometers you can't see anything smaller than 250 nanometers.
Unfortunately in biology that's right where things get interesting says Boyden who is a member of MIT's Media Lab and Mcgovern Institute for Brain Research.
sheds light on how organisms evolve new morphological structures and functions.""For the first time, we have a good understanding of how something completely novel evolves in nature,
as they are able to show much finer details than visible light and their penetrating power allows you to see inside objects,
The size of the smallest details that can be resolved depends on the wavelength of the radiation used.
X-rays have very short wavelengths of only about 1 to 0. 01 nanometres (nm), compared to 400 to 800 nm for visible light.
A nanometre is a millionth of a millimetre. The high penetration of X-rays is favoured for three-dimensional tomographic imaging of objects such as biological cells
#Diode lasers bars with 2 kw output power for ultra-high power laser applications The FBH presented the latest results from their project Cryolaser at CLEO 2015,
demonstrating for the first time that a single 1-cm laser bar can deliver at least 2 kilowatt (kw) of optical output power,
High energy laser applications of the future: these are the target of current diode laser research at the Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik (FBH.
Worldwide, teams of scientists and technologists are working on a new generation of ultra-high energy lasers.
These are tools for basic science, for novel medical applications and, not least, for laser-induced fusion.
Ultra-high power laser systems require diode lasers that are not just extremely capable, but also manufacturable at low costs in very high volumes.
Specifically diode lasers bars in the wavelength range 930 to 970 nm are the fundamental building blocks for pump sources for Ytterbium-doped crystals in large laser facilities,
where optical pulses are generated with petawatt class peak energies and picosecond pulse widths. The individual laser bars in these pump sources have a typical output power between 300 and 500 Watts.
The FBH is currently optimizing both the necessary design and technology as a part of the Leibniz project Cryolaser.
203 K). The performance of diode lasers is improved substantially at these temperatures. Recently, the FBH team led by Paul Crump presented the latest results from Cryolaser in a talk and a tutorial at CLEO 2015 in San jose
Such bars have the potential to play an important role in future high-energy-class laser facilities.
The final pump sources are being evaluated for potential use in high-energy-class diode-pumped solid-state laser systems together with the world-leading groups in the field
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