#Photonic crystal fibre: a multipurpose sensor Glass fibres can do more than transport data. A special type of glass fibre can also be used as a high-precision multipurpose sensor,
as researchers at the Max Planck Institute for the Science of Light (MPL) in Erlangen have demonstrated now("Flying particle sensors in hollow-core photonic crystal fibre").
which can literally sense different physical quantities such as electric field, temperature or vibrations through the inside of this hollow-core photonic crystal fibre.
which flies through the hollow channel in the interior of a photonic crystal fibre to measure different physical quantities, for example the electric field along the optical fibre.
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,
The special properties of photonic crystal fibre, however, enable several applications that are not possible with conventional optical fibres.
whether hollow-core photonic crystal fibres are suitable as sensors by initially using the fibres to measure electric fields, vibrations and temperatures.
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 loss here is proportional to the strength of the electric field, and it is thus possible to determine the field from a distance.
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.
"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,
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."
and could form the basis of optical computing. At its most basic level, your smart phone's battery is powering billions of transistors using electrons to flip on and off billions of times per second.
While lasers can fit this requirement they are too energy-hungry and unwieldy to integrate into computer chips.
This so-called plasmonic device could one day be used in optical computing chips or for optical communication between traditional electronic microchips.
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.
In a seminal paper in the scientific journal Nature Photonics("All-plasmonic Mach-Zehnder modulator enabling optical high-speed communication at the microscale"),Juerg Leuthold, professor of photonics and communications
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.
and Vladimir M. Shalaev, scientific director of nanophotonics at Purdue's Birck Nanotechnology Center and a distinguished professor of electrical and computer engineering."
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.
demonstration version of the tiny camera module for at the SPIE Photonics West exhibition earlier this year, noting that it had the ighest resolution of any camera module with diameter in the 1-2 mm range Speaking
so the receiver is caused free of crosstalk by the Kerr effect. he photonics experiments were performed at UCSD Qualcomm Institute by researchers from the Photonics Systems Group led by Radic.
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.
Could Simplify Photonic crystal Formatio i
#Study: OCT Could Aid Brain tumor Removal Study: OCT Could Aid Brain tumor Removalbaltimore, June 19, 2015 Optical coherence tomography (OCT) holds promise for guiding surgeons as they operate on brain tumors
visit www. indigo-clean. com and www. strath. ac. uk. Biophotonics Market Poised for Growth Top Biophotonics Stories of 2014 Ophthalmology Devices Market Set to
#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.
New Digital Conference Explores Biophotonics Imaging Fluorescent, Magnetic nanoparticles Aid Bioimaging System Combines Optical Microscopy, MRI Bioimaging Technique Isolates Moving Tissu i
#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
first author of the paper reporting the results in the journal Nanophotonics. When these spirals are shrunk to sizes smaller than the wavelength of visible light,
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.
#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,
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,
and have made several copies in their lab. Reporting in Nature Photonics, the team has demonstrated now that these devices worked perfectly,
#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:
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
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.
Dr Mike Macdonald, Head of the Biophotonics research group at the University of Dundee, explained:"
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.
and phase-locking technology developed could be widely applicable with the broader optics/photonics community y
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
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