#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.
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
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.
thus benefit from the new laser material. Gas sensors or implantable chips for medical applications which can gather information about blood sugar levels
#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.
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
#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
Described in The Optical Society (OSA) journal, Optics Express, the new approach involves bouncing laser light off individual bacteria under the microscope,
"Employing laser holographic techniques, we achieved rapid and label-free identification of bacterial species at the single bacterium level with a single-shot measurement,
the group said it had employed ultrafast femtosecond lasers to produce a three-dimensional single crystal capable of guiding light waves through glass with little loss of light.
The article, published May 19, is titled"Direct laser-writing of ferroelectric single-crystal waveguide architectures in glass for 3d integrated optics."
The group says its achievement will boost ongoing efforts to develop photonic integrated circuits (PICS) that are smaller, cheaper, more energy-efficient and more reliable than current networks that use discrete optoelectronic components--waveguides, splitters, modulators, filters
therefore essential for 3d laser-fabrication of PICS to achieve its full potential.""To pattern crystals in glass, the Lehigh-led group employed femtosecond lasers,
whose speed and precision make them useful for cataract and other eye surgeries. A femtosecond is one-quadrillionth,
Pulses emitted by femtosecond lasers last between a few femtoseconds and hundreds of femtoseconds. Scientists have been attempting for years to make crystals in glass in order to prevent light from being scattered as light signals are transmitted,
"The femtosecond laser provides several critical advantages, say Dierolf and Jain. The high intensity of the laser pulse enables nonlinear optical absorption.
The precise focus enables researchers to control where the laser is focused and where light is absorbed."
"We can heat the glass only locally, "says Jain, "creating the desired conditions and causing the glass to melt,
"The unique focus of the femtosecond laser also makes it possible to"write"the crystal inside the glass and not on its surface."
"Somehow, you have to get the laser inside the glass before you turn it on.
We do that by exploiting a property of the femtosecond lasers--that only at the focal point of the laser is there sufficient intensity to cause the change you want."
"If you double the intensity of the laser, you might get 20 to 100 times more absorption.
and ultrafast heat current created by picosecond--one trillionth of a second--pulses of laser light,"Cahill added."
and X-ray Free electron lasers create much brighter X-rays with higher fluxes. Wedged MLLS are expected to enable the maximization of this technology at the atomic scale.
as well as miniature NS honeycomb cells, from nylon using selective laser sintering for experimentation. NS honeycombs can be made from a variety of materials to suit distinct applications.
Arrayat the fair, the FBH exhibits novel dual-wavelength diode lasers that are suitable for use in miniaturized, portable laser measurement systems for Raman spectroscopy applications.
The laser sources alternatingly emit light from only one chip at two different stabilized wavelengths, which are defined by gratings implemented into the semiconductor chip.
Wavelength selection is realized by separately addressable sections within the laser. The innovative diode laser chip is ideally applicable for SERDS (Shifted Excitation Raman Difference Spectroscopy),
enabling to measure Raman spectra under real-world conditions even in highly fluorescent environments and when exposed to daylight.
With these FBH tiny monolithic light sources on chip level, a compact SERDS measurement head that is only as small as a laser pointer was realized for the first time.
Arrayfiber-coupled demonstrators newly developed at FBH for industrial use aim at integrating laser radiation with high spectral brightness into various systems
Now, efficient and compact laser sources are at hand emitting in the near-infrared on multi-watt level (CW operation) with a narrow-band spectrum and a stigmatic, nearly Gaussian laser beam
Such sources are demanded highly for the pumping of solid-state lasers and frequency doubling. On a footprint of less than 10 cm2, the micro module integrates a 1064 nm distributed Bragg reflector (DBR) tapered laser,
a micro-optical assembly designed to maintain brightness and mounted with sub-micrometer precision and temperature-stabilizing components.
Arraythe institute develops highly brilliant diode lasers in a great variety of designs and packages, covering the wavelength range from 630 nm to 1180 nm.
For rapid prototyping applications the FBH has developed DBR ridge waveguide (RW) lasers with 24 individually addressable emitters featuring a wavelength spacing>0. 3 nm and a spectral width<1 pm.
and the Center for Functional Nanomaterials at the U s. Department of energy's Brookhaven National Laboratory, has demonstrated a new process to construct such diamond nanocavities in
The fabrication of the optical cavities relied on a new silicon hard-mask fabrication process that applies mature semiconductor fabrication methods for patterning high-quality photonic devices into unconventional substrates.
#Sweeping lasers snap together nanoscale geometric grids Now, scientists at the U s. Department of energy's Brookhaven National Laboratory have developed a new technique to rapidly create nano-structured grids for functional materials with unprecedented versatility."
Here, an intensely hot laser swept across the sample to transform disordered polymer blocks into precise arrangements in just seconds."
"Our laser technique forces the materials to assemble in a particular way. We can then build structures layer-by-layer,
"Arrayfor the first step in grid construction, the team took advantage of their recent invention of laser zone annealing (LZA) to produce the extremely localized thermal spikes needed to drive ultra-fast self-assembly.
The sweeping laser's heat causes the elastic layer to expand--like shrinkwrap in reverse
"The direction of the laser sweeping across each unassembled layer determines the orientation of the nanowire rows,
"We shift that laser direction on each layer, and the way the rows intersect and overlap shapes the grid.
Now, a team of scientists of the Laser spectroscopy Division of Prof. Theodor W. Hänsch (Director at the Max Planck Institute of Quantum Optics and Chair for Experimental Physics at the Ludwig-Maximilians-Universität Munich) has developed a technique where an optical microcavity is used to enhance the signals
Laser light is coupled into the resonator through this fibre. The plane mirror is moved point by point with respect to the fibre
and neodymium using one of the world's fastest lasers, housed in the UW-Madison geoscience department.
"Heating with traditional lasers gave spurious results.""It took three years to perfect the working of the laser and associated mass spectrometry instruments,
Li says. Previous probes of the source of banded iron had focused on iron isotopes.""There has been debate about
The MSU researchers found that by shooting an ultrafast laser pulse into the material, its properties would change
By varying the wavelengths and intensities of the laser pulses, the researchers were able to observe phases with different properties that are captured on the femtosecond timescale.
"The laser pulses act like dopants that temporarily weaken the glue that binds charges and ions together in the materials at a speed that is ultrafast and allow new electronic phases to spontaneously form to engineer new properties,
Polyu researchers have developed a simplified method for direct analysis of edible oils using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). In the new MALDI-MS
The research, published today in Nature Photonics, was led by Zhenda Xie, a research scientist in the lab of Chee Wei Wong,
"With the help of state-of-the-art high-speed single photon detectors at NIST and support from Dr. Franco Wong, Dr. Xie was able to verify the high-dimensional and multi-degrees-of-freedom entanglement of photons.
in collaboration with Michael Thompson, associate professor of materials science and engineering, got around this issue by using extremely short melt periods induced by a laser.
if the silicon is heated by laser pulses just nanoseconds long. At such short time scales, silicon can be heated to a liquid,
They first used a carbon dioxide laser in Thompson's lab to"write"the nanoporous materials onto a silicon wafer.
Writing lines in the film with the laser, the block copolymer decomposed, acting like a positive-tone resist,
"We are developing photodetectors based on this technology and, for example, it could be helpful for photographers wanting to shoot better quality pictures in weak light conditions,
#Better memory with faster lasers By studying the effect of femtosecond laser pulses on the types of materials used to make DVDS,
When the laser light interacts with a phase-change material, its atomic structure changes from an ordered crystalline arrangement to a more disordered,
"Today, nanosecond lasers--lasers that pulse light at one-billionth of a second--are used to record information on DVDS and Blu-ray disks,
The speed with which data can be recorded is determined both by the speed of the laser--that is,
Thus, with a nanosecond laser,"the fastest you can record information is one information unit
people have started to use femtosecond lasers, which can potentially record one unit every one millionth of a billionth of a second.
when it is hit by a femtosecond laser pulse. In UEC, a sample of crystalline Gete is bombarded with a femtosecond laser pulse,
followed by a pulse of electrons. The laser pulse causes the atomic structure to change from the crystalline to other structures
and then ultimately to the amorphous state. Then, when the electron pulse hits the sample, its electrons scatter in a pattern that provides a picture of the sample's atomic configuration as a function of the time.
the structural shift in Gete caused by the laser pulses. However, they also saw something more:
regardless of the laser speeds used.""Even if there is a laser faster than a femtosecond laser,
there will be a limit as to how fast this transition can occur and information can be recorded, just because of the physics of these phase-change materials,
ROM storage, including CDS and DVDS, uses phase-change materials and lasers to store information. Although ROM records
#Noninvasive device could end daily finger pricking for people with diabetes A new laser sensor that monitors blood glucose levels without penetrating the skin could transform the lives of millions of people living with diabetes.
uses a small device with low-powered lasers to measure blood glucose levels without penetrating the skin.
"At the heart of the new technology is a piece of nano-engineered silica glass with ions that fluoresce in infrared light when a low power laser light hits them.
The work is based on an X-ray laser experiment at the Department of energy's SLAC National Accelerator Laboratory.
X-ray laser Best Tool for Tiny Samples Xu said he first learned about the benefits of using SLAC's X-ray laser for protein studies in 2012.
"Catching Your Eye Fove's eye-tracking technology employs infrared lasers that bounce light off the wearer's retinas to determine how the eyes are angled.
or use a laser. It is capable of working 10 times faster and with more accuracy than a surgeon hands when performing intricate procedures.
#Laser-generated surface structures create extremely water-repellent metals Super-hydrophobic properties could lead to applications in solar panels,
sanitation and as rust-free metals Scientists at the University of Rochester have used lasers to transform metals into extremely water repellent,
Guo and his colleague at the University 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 process is that he structures created by our laser on the metals are intrinsically part of the material surface.
Unlike Guo 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
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.
Guo team had blasted previously materials with the lasers and turned them hydrophilic, meaning they attract water.
Guo team is now planning on focusing on increasing the speed of patterning the surfaces with the laser,
delivering 10 to 100 times faster 3d imaging speeds than laser scanning confocal, two-photon,
Her study is published in the Advance Online Publication (AOP) on Nature Photonics website on January 19,
#New laser could upgrade the images in tomorrow#s technology A new semiconductor laser developed at Yale has the potential to significantly improve the imaging quality of the next generation of high-tech microscopes laser projectors photo
Based on a chaotic cavity laser the technology combines the brightness of traditional lasers with the lower image corruption of light emitting diodes (LEDS.
The new laser is described in a paper in the Jan 19 online edition of the Proceedings of the National Academy of Sciences.
and biomedical engineering and diagnostic radiology. his chaotic cavity laser is a great example of basic research ultimately leading to a potentially important invention for the social goodsaid co-author A. Douglas Stone the Carl A. Morse Professor
and chair of applied physics and professor of physics. ll of the foundational work was motivated primarily by a desire to understand certain classes of lasers random and chaotic with no known applications.
Eventually with input from other disciplines we discovered that these lasers are suited uniquely for a wide class of problems in imaging
when traditional lasers are used. A way to avoid such distortion is by using LED light sources.
The new electrically pumped semiconductor laser offers a different approach. It produces an intense emission
and of physics who is the paper corresponding author. s we showed in the paper the standard edge-emitting laser produced speckle contrast of 50
%while our laser has the speckle contrast of 3%.So our new laser has eliminated completely the issue of coherent artifact for full-field imaging. o-author Michael A. Choma assistant professor of diagnostic radiology pediatrics
and biomedical engineering said laser speckle is a major barrier in the development of certain classes of clinical diagnostics that use light. t is tremendously rewarding to work with a team of colleagues to
and tested the new laser. Lee and Huang grew the laser semiconductor wafer via molecular beam epitaxy
and helped in fabrication and testing. Choma aided in the design and performance criteria for the laser provided expertise in spatial coherence
and speckle in imaging and is working with Redding to apply the laser for full-field imaging at Yale School of medicine.
Stone and Cerjan modeled the laser and analyzed its characteristics e
#Tattoo-like sensor can detect glucose levels without a painful finger prick Scientists have developed the first ultra-thin flexible device that sticks to skin like a rub-on tattoo
and can detect a person glucose levels. The sensor reported in a proof-of-concept study in the ACS journal Analytical Chemistry has the potential to eliminate finger-pricking for many people with diabetes.
A sophisticated laser system sends laser beams into different directions. Therefore different pictures are visible from different angles.
But the crucial point is that the individual laser pixels work. Scaling it up to a display with many pixels is not a problemsays Jörg 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 rixel consists of lasers and a moveable mirror. he 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 directionssays 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 Rice university scientists advanced their recent development of laser-induced graphene (LIG) by producing
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
since their work to make vertically aligned supercapacitors with laser-induced graphene on both sides of a polymer sheet.
It done on a commercial laser system as found in routine machine shops, in the open air. Ripples, wrinkles and sub-10-nanometer pores in the surface and atomic-level imperfections give LIG its ability to store a lot of energy.
Optical metamaterials harness clouds of electrons called surface plasmons to manipulate and control light. Purdue University researchers had created previously uperlatticesfrom layers of the metal titanium nitride and the dielectric,
Research findings are detailed in a cover paper appearing in the Jan 15 issue of Laser & Photonics Reviews.
He and Kildishev are working with a team of researchers led by Vladimir M. Shalaev, scientific director of nanophotonics at Purdue Birck Nanotechnology Center and a distinguished professor of electrical and computer engineering,
Professors Shalaev, Kildishev and Boltasseva are a part of a Purdue reeminent teamworking on quantum photonics.
When exposed to a laser light, the system rises from its round stateto an excited state,
the optical metamaterials owe their unusual potential to precision engineering on the scale of nanometers. Quantum computers would take advantage of phenomena described by quantum theory called uperpositionand ntanglement.
We envisage a new generation of optoelectronic devices to stem from this work, from simple transparent lighting and lasers and to more complex applications.
#New technology makes creating ultrashort infrared laser pulses easy and cheap In a marathon everyone starts at roughly the same place at roughly the same time.
It is possible to use a medium to make a laser pulse shorter. Scientists at the Vienna University of Technology have found a way to compress intense laser pulses by a factor of 20 to just 4. 5 just by sending them through a cleverly designed hollow fibre.
The compressed laser pulse only consists of a single oscillation of light. This tabletop technology is much simpler and cheaper than previously used complicated setups.
It has now been published in ature Communicationshollow Fibre Filled with Gasan infrared laser pulse is sent into a hollow fibre filled with gas.
The nonlinear interaction between the light and the gas atoms in the special fibre makes different wavelengths travel at different velocities.
The combination of these two opposing effects leads to a compression of the laser pulse. It is like sending off a long line of marathon runners
For years extremely short infrared laser pulses have been used to unravel the secrets of the quantum world.
Up until now complicated setups had to be used to create these femtosecond laser pulses. Usually the different wavelengths of the pulse have to be manipulated with intricate mirror systems to compress the pulse.
New Tool for Further Researchin their recent publication the researchers at the Vienna University of Technology have demonstrated already that their laser pulses can be used for highly advanced experiments:
Depending on the exact shape of the laser pulse the electrons ripped away from the xenon atoms can be sent into different directions. t is an ultrafast electron switchsays Tadas Balciunas.
The photonics team at the Vienna University of Technology is planning to use this new technology for a variety of measurements in the future
Having a femtosecond laser system which is cheap small and easy to use could turn out to be a boost for attosecond science and ultrafast laser research in general s
#Nanoscale mirrored cavities amplify connect quantum memories The idea of computing systems based on controlling atomic spins just got a boost from new research performed at the Massachusetts institute of technology (MIT) and the U s. Department of energy (DOE) Brookhaven National Laboratory.
we build an optical cavity trap for photonsround the NV, Englund said. These cavities, nanofabricated at Brookhaven by MIT graduate student Luozhou Li with the help of staff scientist Ming Lu of the CFN, consist of layers of diamond
The device brings researchers closer to producing silicon photonic chips that compute and shuttle data with light instead of electrons.
Electrical and computer engineering associate professor Rajesh Menon and colleagues describe their invention today in the journal Nature Photonics.
The overhead view of a new beamsplitter for silicon photonics chips that is the size of one-fiftieth the width of a human hair.
University of Utah Electrical and Computer engineering Associate professor Rajesh Menon is leading a team that has created the world smallest beamsplitter for silicon photonic chips.
Dan Hixson/University of Utah College of Engineeringsilicon photonics could significantly increase the power and speed of machines such as supercomputers, data center servers and the specialized computers that direct autonomous cars and drones with collision detection.
And because photonic chips shuttle photons instead of electrons mobile devices such as smartphones or tablets built with this technology would consume less power,
The first supercomputers using silicon photonics already under development at companies such as Intel and IBM will use hybrid processors that remain partly electronic.
The team, from the Centre for Nanoscale Biophotonics (CNBP), an Australian Research Council (ARC) Centre of Excellence, created a simple,
A free application to convert your smartphone into a bio-sensing readout device will be available for download from the Centre for Nanoscale Biophotonics web site www. cnbp. org. au/smartphone biosensing c
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