when illuminated by a low-power near-infrared diode laser. The fluorescence decay changes when the glass comes in contact with skin due to glucose in the bloodstream absorbing
The microlenses then illuminated a smalls part of the sample with a lasers and imaged the resulting fluorescence signals.
#Superfast Lasers Create A Hologram You Can Touch The halls of science fiction are decorated well with dreams of hologramsules Verne introduced holography to literature in 1893 with The Castle of the Carpathians,
Now, researchers at the Digital Nature Group (DNG) have found a way to use lasers,
Using femtosecond lasers (a femtosecond is a quadrillionth of a second, and the lasers transmit bursts that last 30 to 270 femtoseconds),
the team can make holograms that are safe to touch. The images are three-dimensional, with resolutions up to 200,000 dots per second.
when the laser's focused energy ionizes the air. When touched the laser feels like sandpaper,
says principal investigator Yoichi Ochiai, although some participants thought the plasma felt a little like a static shock.
This isn't the first attempt at using femtosecond lasers to form air plasma, says Chunlei Guo, professor of optics and physics at the University of Rochester,
but the study should help in designing future femtosecond laser displays. Although previous studies have used nanosecond
and femtosecond lasers to create images, the DNG researchers say preceding studies haven't achieved resolution this high,
Since the lasers fire at such a high speeds they're able to react in realtime,
researchers fired their femtosecond laser through a spatial light modulator, which continues the beam through a series of lenses, a mirror and a Galvano scanner,
which positions a mirror to precisely direct the laser beams. A camera underneath the hologram captures user interaction, allowing the dots to respond to being ouched.
The key to making these holograms safe is the shorter duration of the laser bursts.
if the lasers fired in more than two second bursts, they burnt the leather researchers used to simulate skin.
The laser itself can transmit up to 7w and this 1 cubic centimeter experiment only used 1w of the laser power s
#Machines Sniff out Illegal Specimens Of Wood Illegally traded specimens of endangered species present a huge problem to investigators and customs officials all over the world.
#For the first time, A Laser That Shines Pure White The emission of Arizona State university's white laser.
The laser is a versatile tool in the modern technological arsenal. It can provide immense energy to a precise location at a very specific wavelength,
lasers emit light at a single specific wavelength. Until now. A team from Arizona State university has built a white laser that simultaneously fires in red, green and blue, covering more than 90 percent of the colors perceptible to the human eye.
The laser is modulated by a synthetic nanosheet, a multi-segmented, layered material that can emit in red, green,
and blue light in different proportions, based on the light applied to each segment. The wavelength spans 191 nanometers,
which the study claims is reported the largest for a laser of this kind. Researchers rewthe material
Real color images, under low light, of a single laser beam. So, we have a white laser.
What does that mean? Well, lasers are being used more and more in transparent laser displays, even garnering interest from Apple.
Being able to reproduce the color white with a laser is huge step towards making these technologies more viable.
These lasers also have immense possibility in data transfer. Wireless data transfer using light has already been demonstrated at blistering gigabit speeds using white LED LIGHTS.
Lasers are already an improvement over LEDS, because Li-Fi works by reading slight modulations of light,
and lasers can be tuned far more finely than LEDS. White light allows those signals to be transmitted over multiple areas of the color spectrum
which is effectively adding more pathways for data to travel. The ASU team calls their white laser he ultimate form of such a light
#New Sun-Blocking Material Uses Compounds From Algae And Fish Researchers have used compounds found in algae
For example, when they are illuminated with infrared laser light, they emit visible blue light. A number of crystals produce this effect, called frequency doubling or harmonic generation, to various degrees.
When infrared laser light strikes the tiny spirals, it is absorbed by electrons in the gold arms.
The spirals also have a distinctive response to polarized laser light. Linearly polarized light, like that produced by a Polaroid filter, vibrates in a single plane.
when circularly polarized laser light is used. In circularly polarized light, the polarization plane rotates either clockwise or counterclockwise.
#Researchers create holograms you can touch using high-powered lasers Three-dimensional, interactive holograms are now a reality,
ultra-quick lasers to produce holograms that can be physically felt and respond to human touch.
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.
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.
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 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."
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:
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.
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.
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.
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.
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,
"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
i e. we can make this system transparent again by adding another laser at a specially chosen wavelength nearby.
The material was made in a single steel sheet using lasers to engrave"chiral, "or geometric microstructure patterns,
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.
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.
Guo's team had blasted previously materials with the lasers and turned them hydrophilic meaning they attract water.
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
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.
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.
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."
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."
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
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,
#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
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