Two laser beams manoeuvre a microbead through a hollow glass fibre In photonic crystal fibres (PCFS), which were invented around 20 years ago by Philip Russell, Director at the Max Planck Institute for the Science of Light,
This was achieved by sending a laser beam through the channel from each end of the fibre.
By setting the power of the two laser beams to different strengths, the bead was pushed in one direction slightly more than in the other and moved through the fibre at a specific speed.
and thus reflects more laser light to the side than in the normal position. This light attenuation is measured by a photodiode at one end of the fibre.
the physicists illuminate the bead with an additional, weak laser. They use the Doppler effect here,
as the laser light experiences losses as it is transmitted in the PCF, and thus the glass bead can no longer be trapped above a certain length.
The condensate is created by first exciting a sufficient number of polaritons using a laser and then observed via the blue light it emits.
The condensate is created by first exciting a sufficient number of polaritons using a laser and then observed via the blue light it emits.
Toward future polariton lasers and optical transistors In a condensate, the polaritons all behave the same way, like photons in a laser.
The study of room-temperature condensates paves the way for future technological breakthroughs such as polariton micro-lasers using low-cost organic materials,
and require less activation power than conventional lasers. Powerful transistors entirely powered by light are another possible application.
so that the external laser used for pumping could be replaced by more practical electrical pumping. Fertile ground for studying fundamental questions According to Professor Maier, this research is also creating a platform to facilitate the study of fundamental questions in quantum mechanics."
While lasers can fit this requirement they are too energy-hungry and unwieldy to integrate into computer chips.
When a laser shines on the surface of a silver cube just 75 nanometers wide,
"There is great interest in replacing lasers with LEDS for short-distance optical communication, but these ideas have always been limited by the slow emission rate of fluorescent materials,
"The heating or cooling could be done locally with lasers, tiny heaters, or thermoelectric devices placed at specific locations in the microfluidic devices.
Modern telecommunications use laser light with a wavelength of one and a half micrometers, which accordingly is the lower limit for the size of a modulator.
For instance, a laser beam can be split onto two arms by a beam-splitter and recombined with beam combiner.
In optical communications, laser pulses are used to transmit information along fiber-optic cables for telephone service, the Internet and cable television.
Exposing the material to a pulsing laser light causes electrons to move from one energy level called the valence band to a higher energy level called the conduction band.
The pulsing laser light changes the AZO's index of refraction, which, in turn, modulates the amount of reflection
"The storage mechanism in DVDS is based on the fact that laser pulses rearrange the structure of the material,
laser pulses can convert it very quickly from a strongly reflective crystalline state into a much less reflective disordered version..
If it were possible to extract the energy of the infrared laser pulse before the crystal has melted
This is precisely what the researchers do with a short, intense laser pulse, with the direct consequence that the material no longer absorbs light as well,
and thus in the optical properties by firing a second, also very short pulse onto a thin sample of GST after the first laser pulse.
Since the researchers also sent the electrons after the exciting laser pulse with a different delay
#Laser'tricorder'can diagnose malaria through the skin It's a weapon that fights malaria a laser scan can give an accurate diagnosis in seconds,
The laser's wavelength doesn't harm human tissue, but is absorbed by hemozoin waste crystals that are produced by the malaria parasite Plasmodium falciparum
An oscilloscope placed on the skin alongside the laser senses these nanoscale bubbles when they start popping,
But Lapotko's team is confident it can overcome this effect by switching to a different wavelength of laser
#Infrared light speeds up healing by turbocharging our cells A near infrared laser beam makes it easier for a nanoscale probe to pass through water (Image:
#Living lasers made by injecting oil droplets into human cells Light fantastic (Image: Matja Humar and Seok Hyun Yun) Individual cells have been turned into tiny lasers. t actually super-easy,
says Matja Humar of Harvard Medical school. The feat allows cells to be labelled and monitored more accurately,
forming an optical cavity which could be filled with fluorescent dye. Shining a light pulse on to the cavity excited the dye atoms into emitting light in a tightly focused beam.
they performed the same function as the oil droplets, emitting laser light when excited. The final way involved exploiting the fatty droplets that exist naturally within living cells. e all have these fat cells inside our tissue.
We are made all of lasers, says Humar. The first two approaches were tested on human cells, the last on pig cells.
However laser light is characterised by having an extremely narrow range of wavelengths. That means it is theoretically possible,
to give every single cell in the human body a unique, identifiable laser signature, Humar says.
which focuses exclusively on the macrophage route to converting cells into lasers, goes further in laying out its potential applications.
The contracts leveraged 3ds Selective laser sintering and Direct Metal 3d printing capabilities to meet the high standards of production demanded by the US Air force.
and of applications for terahertz technologies, underscored by a busy panel session at the LASER World of Photonics show in Munich.
potentially offering advantages over laser-scanning confocal, two-photon and light-sheet microscopy. Developed by Columbia University professor Dr. Elizabeth Hillman and graduate student Matthew Bouchard,
Using a 488-nm laser, it cannot penetrate tissue as deeply as two-photon microscopy.
#Ultrafast Lasers Create 3-D Crystal Waveguides in Glass Ultrafast Lasers Create 3-D Crystal Waveguides in Glassbethlehem, Pa.
June 9, 2015 Femtosecond laser pulses can create complex single-crystal waveguides inside glass a discovery that could enable photonic integrated circuits (PICS) that are smaller, cheaper, more energy-efficient and more reliable than current networks that use
"A polarized light field microscope image shows crystal junctions written inside glass with a femtosecond laser.
#Laser-Writing of DVDS May have a Speed limit Phase-change materials used in DVDS and other digital storage media pass through a previously unknown intermediate atomic state under laser pulses.
The discovery could lead to faster computer memory systems with larger storage capacity but may also point to an unavoidable limit to data recording speeds, according to researchers at the California Institute of technology.
or amorphous, configuration when illuminated with laser pulses. These two states represent the ones and zeroes of digital data.
The speed with which data can be recorded is determined both by the laser's pulse width
With a nanosecond laser,"the fastest you can record information is one information unit, one 0 or 1,
people have started to use femtosecond lasers, which can potentially record one unit every one millionth of a billionth of a second.
which allowed them to observe directly the transitioning atomic configuration of a prototypical phase-change material, germanium telluride (Gete), under femtosecond laser pulses.
The technique directs a pulse of electrons at the material after each laser pulse to create pictures of the sample's atomic configuration over time.
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,"said postdoctoral scholar Giovanni Vanacore."
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
#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
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
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