#First boson laser could save power Stanford university University of Michigan rightoriginal Studyposted by Bjorn Carey-Stanford on May 24 2013stanford (US)# Scientists have demonstrated a revolutionary electrically driven polariton laser
that could significantly improve the efficiency of lasers. The physics powering lasers has remained relatively unchanged through 50 years of use.
The new system however makes use of the unique physical properties of bosons subatomic particles that scientists have attempted to incorporate into lasers for decades.#
#We ve solidified our physical understanding and now it s time we think about how to put these lasers into practice#says physicist Na Young Kim a member of the Stanford university team which was led by Yoshihisa Yamamoto professor of electrical engineering and of applied physics.#
#This is an exciting era to imagine how this new physics can lead to novel engineering.#
#Electrically driven polariton lasers Kim says would operate using one-hundredth of the power of conventional lasers
Einstein s predictionall lasers are based on Einstein s principle of stimulated emission. Charged particles such as electrons exist in discontinuous energy levels like rungs on a ladder.
A laser keeps this process going by continually providing energy for electrons to move into higher energy levels.
and conventional lasers waste energy unnecessarily exciting electrons to higher energy levels even when the lower levels are too full to accept the excited electrons
Exciting excitonskim s polariton laser however pairs electrons with so-called#holes#to form another type of particle an exciton.
Using bosons in lasers has been a scientific goal for decades but Yamamoto s team is the first to successfully build an electrically driven laser using bosons.
The result was reproduced recently and confirmed by scientists at the University of Michigan who published their work in the journal Physical Review Letters.)
This change drastically reduces the amount of power required to run the laser. The current iteration of the polariton laser requires two to five times less energy than a comparable conventional laser
but could require 100 times less energy in the future.##The outcome would look similar to that of the traditional photon lasers
but the physical mechanisms inside are very different#Kim says. The laser consists of an electron reservoir and a hole reservoir.
When a current is applied electrons and holes come together to form excitons in excited energy levels.
#One benefit of the electrically driven polariton laser is it only needs to be attached to a power supply to emit photons allowing it to be integrated easily with existing semiconductor chips in the future.
Still too coolthe current polariton laser can run only at a chilly 4 degrees Kelvin (minus 452 degrees Fahrenheit)
The team hopes switching to a material that requires more energy to break apart excitons will allow them to build polariton lasers that work at room temperature an important step toward widespread use.#
#We re hoping we can replace conventional semiconductor lasers with these polariton lasers in the future#Kim says.#
#Stanford researchers are already using the polariton laser to develop quantum computers and quantum simulators. Kim believes similar lasers will be available to those outside the scientific community within the next five to 10 years.
Researchers conducted the work in collaboration with the National Institute of Informatics in Tokyo Japan and a team from the University of W##rzburg in Germany led by physicist Alfred Forchel.
Lasers software and a joystick After spending several years interviewing scientists and holding public forums to debate ethics and air concerns,
Rather, it a highly advanced single-cell micro-surgery, replete with cutting-edge lasers and imaging software and, yes, even a joystick,
and Sciences University just outside Portland. his procedure uses a very high-tech imaging system microscopes, lasers,
The light from a low-power infrared laser interacts with the atoms and is transmitted through the fiber-optic cable to register the magnetic field strength.
and docks with the teats using a 3d camera and lasers. Another feature is a set of counter-rotating brushes that automatically clean the teats of dirt
#NASA probe will reveal 3d architecture of forests from space NASA is developing a laser-based instrument for deployment on the International space station that will probe the depths of Earth's forests from space in a bid to reveal more about their role in the planet's carbon cycle.
After its completion in 2018, this Global Ecosystem Dynamics Investigation (GEDI) lidar will join the likes of the Soil Moisture Active Passive satellite in studying Earth's vegetation on a global scale."
"GEDI carries three specialized lasers and an optics system that divides the three beams into 14 tracks on the ground.
The lasers will send brief pulses of light around 16 billion of them in a year that are optimized to pass through the canopy of even very dense forests without causing harm to animals or vegetation,
The GEDI lidar will be built at NASA'S GODDARD SPACE FLIGHT CENTER, with the University of Maryland, College Park leading the project e
#Nature inspires color-sensitive CMOS-compatible photodetector Researchers at Rice university's Laboratory for Nanophotonics (LANP) have developed a new image sensor that mimics the way we see color by integrating light amplifiers and color
and other photodetectors used in cameras. Conventional image sensors work by first converting light into electrical signals then combining that information with the red green
LANP graduate student Bob Zheng set out to create a photonic system that could detect colored light but in what lab director Naomi Halas calls a great example of the serendipity that can occur in the lab he wound up with a device with far broader applications.
Zheng's color photodetector consists of an ultra-thin oxide coating atop a thin layer of aluminum that was deposited onto a silicon photodetector using a common technique called electron-beam evaporation.
and the width and spacing of the slits the device is able to preferentially direct different colors into the silicon photodetector
The plasmonic gratings don't just help the photodetector filter color; they also interact with each other thereby increasing the amount of light absorbed (and thus potentially reducing noise.
The scientists replicated these boundaries in glass microscope slides using lasers to engrave networks of wavy 3d micro-cracks within them.
and the company Trilite Technologies have developed a new kind of display just for this purpose that sends beams of light directly to the viewerseyes via a laser and a sophisticated mirror system.
"as the team calls them) used by the prototype system consists of lasers and a movable mirror to send light beams in different directions,
"The mirror directs the laser beams across the field of vision, from left to right,"says Professor Ulrich Schmid of TU Vienna."
"During that movement the laser intensity is modulated so that different laser flashes are sent into different directions.''Unlike current large-scale 3d projection systems,
such as those used at the cinema where only two different pictures are projected, one for each eye,
"But the crucial point is that the individual laser pixels work. Scaling it up to a display with many pixels is not a problem."
and other sophisticated methods, including etching identification codes on produce with lasers or micro-percussion markers that make tiny indents. hey each believe they have the holy grail product tracking solutions sitting in their laptop,
With laser rangefinders and stereo cameras for vision, hydraulically actuated aluminum and titanium limbs and fully articulated humanlike hands, Atlas is envisioned as a humanoid hero who can walk undaunted into dangerous environments
The 3d printed metal gun was constructed using a laser sintering process capable of shaping tougher metals like stainless steel.
The window-mounted device uses a high-frequency laser microphone to pick up bothersome sounds then sends out sounds of its own at 180 degrees,
Blinding lasers Desert Wolf s website states that its Skunk octacopter drone is fitted with four high-capacity paintball barrels, each capable of firing up to 20 bullets
000 bullets at a time as well asblinding lasers and onboard speakers that can communicate warnings to a crowd.
The second paper presents designs that show how to build electrical components (such as resistors, inductors, capacitors, sensors and actuators) with self-folding laser-cut materials.
#New 3d printed materials lighter than water and as strong as steel A Nanoscribe 3d printer can print models of the Empire state building in a space the width of a human hair using precision lasers.
The printer s mirror-focused laser shines on and hardens a droplet of liquid plastic on a slide.
A computer moves the plate under the laser, selectively hardening it, layer by layer, to match a digital 3d model.
#Panorama Synergy demonstrates viability of Lumimems Reader Panorama Synergy announces that through extensive laboratory testing it has demonstrated the viability of its unique laser-based Optical Readout System, the Lumimems Reader.
and therefore more accurate, is an optical system using a laser directed at a MEMS sensor.
and the need to precisely align the laser with the tip of the tiny MEMS sensor.
#Navy's futuristic laser weapon ready for action The laser has a variety of attack modes,
The 30-kilowatt laser weapon system (Laws) is housed aboard the USS Ponce, a naval vessel stationed in the Arabian Gulfa body of water located south of Iraq that separates the Saudi arabian peninsula from Iran.
Sailors operate the laser using a video game-type controller according to Navy officials. With this controller, they can perform a variety of operations.
the laser can deter the threat with an effect known as optical"dazzling.""This nonlethal option which amounts to a very bright glare is meant to serve as a warning,
sailors aboard the Ponce can increase the strength of the laser's highly concentrated beam,
heat and humidity conditions that aren't ideal for the operation of a laser. The data collected from these trial runs will be used to develop new laser weapons for the Navy under the Office of Naval Research's Solid-state laser-Technology Maturation program.
These future lasers could one day be deployed on both large destroyer ships (used to launch missiles) and smaller combat ships
Navy officials said. Laser weapons systems like the one aboard the USS Ponce could be used in ground-based defense systems,
they first generated entangled photons by converting a laser beam into pairs of photons that were in opposite polarization states
In the future, this could lead to inexpensive microscopes that use ordinary lasers to get this resolution,
To create the effect researchers used lasers to etch nanoscale structures into the metal surface that repel the water.
#Rice-sized laser could be a breakthrough in quantum computing A microwave laser also called a"maser"has been built by Princeton researchers
#Nevertheless, using a combination of atom interferometry and ultra-precision laser techniques, M#ller and his team have,
or tiny laser-photon impacts, which slow the Compton cycles by a precisely known amount.
could serve as the foundation for a new definition of the kilogram tied to a precise laser frequency.
giving materials scientists a new tool for investigating the behaviour of light in the interiors of the complex nanostructures used in lasers, light-based circuits and solar cells."
and in the ultra-small cavities of photonic crystals#components of chip-based lasers and light-emitting diodes."
later it may target the laser, semiconductor and solar-cell industries. He realizes that, by selling the system,
Using lasers and magnetic fields they kept the individual atoms in a lattice arrangement. At positive temperatures, the atoms repel,
But the team also adjusted the trapping laser field to make it more energetically favourable for the atoms to stick in their positions.
The company s technology is a three-by three-millimeter microelectronic chip (0. 1-millimeter thick) containing about 1, 500 light-sensitive photodiodes,
Stanford university researchers are in the early stages of developing self-powered retinal implants where each pixel in the device is fitted with silicon photodiodes.
Patients would wear goggles that emit near-infrared pulses that transmit both power and data directly to the photodiodes.
The researchers reported on the plausibility of their design in the May 2012 issue of Nature Photonics,
describing in vitro electrical stimulation of healthy and degenerate rat retina by photodiodes powered by near-infrared light.
or after being sintered by a laser#into a particular structure. So-called"bioprinters naturally use cells rather than plastics to create organic structures.
#Floating, Touchable'Fairy Lights'Unveiled A team of researchers from Japan has found a way to use a high-speed laser to create a touchable plasma display in mid-air.
Unlike many laser lights, these don produce a burning sensation when touched. By upping the speed of the laser from a nanosecond to a femtosecond
--which is one millionth of one billionth of one second--the researchers have increased the level of safety
These lasers do, however, generate haptic sensations, or hock wavesthat feel like an mpulse on the finger
Laser Technique Etches Water Repellence Into Metalthe team of researchers from the University of Tsukuba, Utsunomiya University,
Nagoya Institute of technology and the University of Tokyo believe their laser-induced plasma, which they've dubbed"Fairy Lights,
Laser-induced plasma can also be controlled precisely. The researchers behind the project believe the technology has several applications,
Laser Levitates Diamondsalthough the displays right now are tiny, at just eight cubic millimeters, there hope that they will become larger as the technology progresses.
Researcher James Anstie at the University of Adelaide and his team are developing an instrument theye dubbed an optical dog nose that uses a specialized laser known as an optical frequency comb to provide a quick and noninvasive way to analyze a person
Anstie and his team shine the laser onto a sample of gas. Since each molecule in the universe absorbs light at different optical frequencies,
the laser system uses light to ensethe range of molecules that are present in the sample,
As for future plans, Anstie of the University of Adelaide Institute for Photonics and Advanced Sensing expects to have a working prototype of the device within three years and a market-ready product within five years.
the S3 center emits a glow when struck by a pulse of laser light. Scientists can then use the lifetime of the resulting luminescence to calculate the temperature of the probe:
#Scientists arm cells with tiny lasers In a feat of miniaturization that makes your Apple Watch look lame,
scientists have implanted tiny lasers within living cells. The lasers can be used to track individual cells for days and weeks,
the researchers report this week in Nano Letters. A laser requires two things: a material that can be stimulated in some way to produce light
and a"resonant cavity"that will ring with light waves of particular wavelengths much as an organ pipe will ring with sound waves of distinct frequencies.
greatly amplifying the light to create a laser. Researchers had used previously living cells to fashion lasers by loading the cells with fluorescent proteins
and placing them within a resonant cavity. Now, a team of physicists and biologists have gone a key step further,
coaxing a cell to envelop a tiny plastic sphere that acts like a resonant cavityhown in green in the micrograph abovehus placing a whole laser within a cell.
triggering laser action and amplifying itself. Crucially, each laser shines at a couple of distinctive wavelengths depending on the precise size of the sphere,
as shown in the graph. So although demonstrated only in cultured cells, the technique might someday be used to track the movement of individual cells,
of which trapped photons using laser pulses in a fibre optic-cable cable. The team claimed this had produced Hawking radiation
The team used one laser to confine the BEC to a narrow tube and another to accelerate some of it faster than the speed of sound.
and forth between the inner and outer horizons triggering the creation of more Hawking phonons each time much like a laser amplifies light.
Physicists call this effect a black hole laser The Hawking radiation exponentially grows it self-amplifies Steinhauer says.
The device looks like a funky golf club with a laser at the end says PG&E spokesperson Hailey Wilson.
#Largest laser gives diamond a record-setting squeeze Diamond has been subjected to the wrath of the world's largest laser
Using the National Ignition Facility (NIF) at Livermore Smith's team bombarded tiny targets with 176 laser beams to put the squeeze on diamond.
and then precisely timed laser pulses to strike the cylinder's interior walls. This caused the gold to emit an avalanche of X-rays that bombarded the stone triggering powerful compression waves inside it.
Laser signals carry more data but the light is almost undetectable by the time it reaches Earth. Now a nanoscale light detector could make such deep-space missives easier to read.
Laser communication is one of the technologies we are considering says Bas Lansdorp CEO of the Mars One project which aims to place a human colony on Mars by 2025.
This development by NIST makes long-distance laser communication even more interesting g
#Japan's huge magnetic net will trawl for space junk SOMEWHERE in Earth's orbit a satellite explodes into a terrifying cloud of debris. Moments later Sandra bullock
#NASA orbiter will use laser to bring broadband to moon The man in the moon is about to get his own version of a broadband connection as well as a visit from China.
NASA's LADEE moon orbiter due to launch on 7 september will use laser pulses to exchange high-capacity signals with Earth.
So LADEE will carry a laser with a near-infrared wavelength that is thousands of times shorter as part of the Lunar Laser communication Demonstration experiment.
Laser beams do not spread out as much as radio waves while they travel which means that they must be aimed very precisely at detectors on the ground.
Earth's atmosphere including clouds can also thwart laser signals. To maximise the chance of cloudless skies LLCD will be able to beam its light to any of three detectors in New mexico California or Spain.
or so of LADEE's planned four months in lunar orbit but a follow-on mission called LCRD will test laser links from Earth orbit for two years beginning in 2017.
Choreographed high-power lasers or electron beams can fuse and sculpt metal powders into high-performance machine parts.
Instead Gianluca Sarri at Queen's university Belfast UK and colleagues used rapid laser bursts to make positrons in their smaller budget device.
The laser pulse ionises inert helium gas generating a stream of high-speed electrons. This electron beam is directed at a thin metallic foil
In 2008 scientists at the Lawrence Livermore National Laboratory in California produced large quantities of antimatter by directing an extremely powerful laser at a tiny gold disc.
They needed much stronger lasers and those lasers are expensive. Also they produced streams of positrons that were extremely broad
whereas our jet is a hundred times narrower and remains pencil-like as it propagates he adds.
laser signals could make it possible to build smaller, lower powered satellites that can still talk to the ground easily."
the researchers developed a prototype device by using a laser to cut a hole in a silicone tube to add drugs. ight
The material is a two-dimensional metallic dielectric photonic crystal and has the additional benefits of absorbing sunlight from a wide range of angles
The material is made from a collection of nanocavities and you can tune the absorption just by changing the size of the nanocavities Chou says.
Another key characteristic of the new material Chou says is that it is matched well to existing manufacturing technology.
and had avoided the side of the chamber where their hippocampal cells were activated by the laser now began to spend more time in that side
a robot made almost entirely from parts produced by a laser cutter that folds itself up
which would self-assemble from laser-cut materials when uniformly heated. The new work is similar
The robot is built from five layers of materials all cut according to digital specifications by a laser cutter.
After the laser-cut materials are layered together a microprocessor and one or more small motors are attached to the top surface.
Zhu shone a laser through the material while tilting the pillars at various angles and found she could control how much light passed through based on the angle at which the pillars bent.
The sensor of a digital camera consists of an array of photodetectors millions of them, even in commodity devices.
so that it reads off the measurements of one row of photodetectors at a time. Ordinarily, that not a problem
In this case the laser performs dual functions. We use two different light pulses: one to modify the material and one to measure the electrical conduction.
to allow laser pulses to pass through it. This all-optical method avoids the need for adding extra electrical contacts to the graphene.
which causes the conductivity to decrease when the electron temperature increases under the illumination of the laser pulse.
#Making the cut Diode lasers used in laser pointers barcode scanners DVD players and other low-power applications are perhaps the most efficient compact and low-cost lasers available.
Attempts have been made over the years to amplify the brightness of these valuable lasers for industrial applications such as welding and cutting metal.
But boosting power usually means decreasing beam quality or focus. And the beam never gets intense enough to melt metal.
Now MIT Lincoln Laboratory spinout Teradiode is commercializing a multikilowatt diode laser system that s bright enough to cut
and weld even through a half-inch of steel at greater efficiencies than today s industrial lasers.
The 4-kilowatt Terablade runs on a novel power-scaling technique developed at MIT that manipulates individual diode laser beams into a single output ray.
This allows for boosting power of a diode laser while preserving a very focused beam. The Terablade has comparable beam quality as compared with traditional manufacturing lasers such as carbon dioxide disk
and fiber says Teradiode cofounder and vice president Robin Huang a former Lincoln Laboratory researcher and Terablade co-inventor.
However because the Terablade is a direct-diode laser it has the highest efficiency and lowest cost of ownership as compared with these other lasers.
Huang says Terablade represents a third generation of industrial lasers. The first generation which evolved a few decades ago was carbon dioxide lasers in
which electricity runs through a gas to produce light. These are very bright but can be as large as trucks
and operate at about 20 percent efficiency. Then came diode-pumped solid-state (DPSS) lasers including disk
and fiber that first transfer energy from diode lasers into a medium usually a crystal before converting it into a laser beam.
These operate only up to about 30 percent efficiency. But the Terablade aptly called a direct-diode laser uses light directly from the diodes skipping the DPSS conversion step
and saving energy Huang says. This means the Terablade operates with just as much power and brightness as all other industrial lasers about 2600 megawatts per square centimeter per steradian at roughly 40 percent efficiency.
At the core of the Terablade is a power-scaling technique known as wavelength beam combining (WBC
Diode lasers are tiny semiconductor devices that when electrically charged cause electrons to create photons of the same wavelength
When fed through an output collimation lens this creates a ray of laser light. An individual diode laser in say a laser pointer can emit a beam in infrared
and near-infrared wavelengths that can be focused tightly to a very small spot but with little power Huang explains.
In the early 2000s Huang Chann and Lincoln Laboratory colleagues built a few prototype lasers based on WBC technology.
One which reached a power level of 50 watts was a world s record for diode laser brightness at that time Huang says.
The company s current CEO is photonics entrepreneur Parviz Tayebati. Today the WBC-based Terablade is a laser module that contains diode laser bars (long arrays of diode lasers) a transform lens a diffraction grating and an output lens.
The light from the diode lasers passes through a transform lens onto the carefully positioned diffraction grating a plate of glass scratched with parallel lines.
However instead of dispersing light at different angles which it s designed to do the grating forces the beams into the same direction superimposing them on one another.
There are a few other multikilowatt direct-diode lasers but they run on another popular and similar power-scaling technique called side-by-side
As the number of diode lasers increases the beam quality degrades resulting in a large focused spot limiting the beam s intensity.
This means the Terablade outputs a beam roughly 100 times brighter than these scaled-up direct-diode laser models Huang says.
a 3-foot cube that comes with multiple laser engines a control computer power supplies and an output head for welding
Other customers include top global builders of industrial laser-based machines and system integrators. More broadly our vision is to revolutionize the laser industry Huang says by introducing powerful direct-diode lasers to various applications across the globe.
In the future he adds the company is also looking toward defense applications. One idea is to build a laser that acts as a heat-seeking missile deterrent:
It fires infrared laser light at the missile which would confuse the missile s programming and cause it to lose its target.
The laser s compact design would allow it to be mounted on a fighter jet. With the Terablade technology Huang says The sky is the limit literally y
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