What’s the News: Scientists have developed the first biological laser, made from a single living cell. This “living laser,” described in a new study in Nature Photonics, could one day lead to better medical imaging and light-based treatments for cancer or other diseases.

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What’s the News: Metamaterials could improve wireless power transfer, letting us one day charge our devices without the hassle of cords and wires, says a study published last week in Physical Review B. While wireless power transfer already works to for tiny amounts of energy, metamaterials could theoretically be used to safely and efficiently boost the technique to handle more power, such as microwaves and lasers.

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What’s the News: In a demonstration near California’s San Nicholas Island last Wednesday, scientists with the U.S. Navy tested a laser weapon aboard the USS Paul Foster by shooting a 15-kilowatt beam at an inflatable boat from a mile away, causing the outboard engines to burst into flames. It was the world’s first successful water-test of a high-energy laser. “I spent my life at sea,” Rear Adm. Nevin Carr told Wired, “and I never thought we’d see this kind of progress this quickly, where we’re approaching a decision of when we can put laser weapons on ships.”

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Light is pushy. The physical pressure of photons is what allows for solar sail space missions that ride on sunlight, and what allows for dreams of lasers that will push those sails even faster. And light can trap objects, too: Optical tweezers can hold tiny objects in place. Pulling an object with light, however, is another matter. Though it’s counter-intuitive to think you could create backward-tugging force with a forward propagating laser and create a real-life tractor beam, the authors of a new physics paper write that they have shown a way it could be done.

Jun Chen’s research team says that the key is to use not a regular laser beam, but instead what’s called a Bessel beam. Viewed head-on, a Bessel beam looks like one intense point surrounded by concentric circles—what you might see when you toss a stone into a lake. The central point in a Bessel beam suffers much less diffraction than a standard laser, and so scientists can use them for precision operations like punching a hole in a cell.

If such a Bessel beam were to encounter an object not head-on but at a glancing angle, the backward force can be stimulated. As the atoms or molecules of the target absorb and re-radiate the incoming light, the fraction re-radiated forward along the beam direction can interfere and give the object a “push” back toward the source. [BBC News]

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The anti-laser—a tech with such a cool name it doesn’t need an obvious application—first came to our attention last year when Yale’s A. Douglas Stone proposed the idea. Now Stone is back with the real thing. His new paper in Science documents the world’s first anti-laser.

Conventional lasers create intense beams of light by stimulating atoms to spit out a coherent beam of light in which all the light waves march in lockstep. The crests of one wave match the crests of all the others, and troughs match up with troughs. The anti-laser does the reverse: Two perfect beams of laser light go in, and are completely absorbed. [Wired]

Anti-lasers are a bit of a funny concept, because anybody who has worn black on an August afternoon knows that absorbing light and turning it into heat isn’t a problem. But creating a device that matches the concentrated beam of a laser and traps more than 99 percent of it—essentially reversing a laser—is an engineering feat.

Whereas a laser uses mirrors to bounce light back and forth through an amplifying material to concentrate it, the anti-laser, as the name would suggest, does basically the opposite.

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With the space shuttles soon bound for retirement homes, NASA is dreaming up the future of U.S. human space flight. Recently, NASA has divulged its interest in two new gadgets: rockets launched via lasers and reusable, manned, deep-space crafts. Now, all the agency needs is a plan to get more money from the government to actually build these things.

The lasers (or possibly microwaves) would be ground-based, and would shoot through the air to energize a rocket’s heat exchanger; elevating the rocket’s fuel to over 3,100 degrees Fahrenheit would give it more thrust.

“The objective is to reduce the cost of getting into space. The way this rocket works, it has a more energetic propulsive system than one where you have fuel and oxidizer that release energy,” Carnegie Mellon University’s Kevin Parkin, head of the Microwave Thermal Rocket project at NASA’s Ames Research Center in California, told Discovery News. [Discovery News]

Although the laser-powered rocket system would be expensive to build, it would reduce launch costs in the long haul.

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The long wait is over: Scientists have achieved laser-driven mind control over moving, squirming worms.

Taking advantage of the emerging technique of optogenetics, Harvard researchers report in the journal Nature Methods that they can target any individual neuron of the tiny transparent worm C. elegans, whether the creature is moving or at rest, and zap it with a laser to see what the particular cell does—move the worm to the left or right, or even cause it to lay eggs.

The whole process, from finding the cell to light hitting its target, takes about 20 milliseconds. As the worm’s position changes, that information is fed back into the computer program, and the laser is adjusted. If the worm crawls too far, a motorized microscope stage brings the animal back. One of the biggest benefits of the new method, [biologist William] Ryu says, is that it works in a roving animal. “The worms are not held down in any way — they’re freely moving. There aren’t many systems where you can look at such truly free organisms.” [Science News]

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This summer, Japan’s golden solar sail unfurled in space, becoming the first successful mission to sail on the physical pressure of the sun’s radiation. Its success led dreamers like Planetary Society director Bill Nye to envision a future of machines pushed forward by the pressure of lasers to explore the cosmos. And now, down here on Earth, researchers say they have demonstrated one of the key principles needed to realize such a vision: a “lightfoil” that uses light to create lift.

The lightfoil described in Nature Photonics is only micrometers in scale, but lead researcher Grover Swartzlander argues that it shows scientists can create and control optical lift. It operates on the property of refraction–how glass bends light.

Optical lift is different from the aerodynamic lift created by an airfoil. A plane flies because air flowing more slowly under its wing exerts more pressure than the faster-moving air flowing above. But in a lightfoil, the lift is created inside the object as the beam shines through. The shape of the transparent lightfoil causes light to be refracted differently depending on where it goes through, which causes a corresponding bending of the beam’s momentum that creates lift. [Science News]

This neat trick could potentially be used to steer a spacecraft, the researchers say.

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A new camera being developed at MIT has the ability to see around corners–without the use of periscopes or mirrors.

The camera works by bouncing ultra-short bursts of laser light off a solid surface (like a floor or an open door). Most of the light is reflected back to the camera, but some scatters in every direction, a small portion of which then hits and bounces off the object to be visualized (and other parts of the scene). Some of that scattered light then bounces back off the door or floor, and finally make its way back to the camera.

“It’s like having x-ray vision without the x-rays,” said Professor Ramesh Raskar, head of the Camera Culture group at the MIT Media Lab and one of the team behind the system. “But we’re going around the problem rather than going through it.” [BBC News]

The team’s computer program can analyze the scattered light and re-create a picture of what is lurking around the corner. The secret to the technology is to not overwhelm the camera’s sensors with the initial reflection from the door. The camera’s shutter has to wait until this initial pulse has passed before trying to collect the light bouncing around.

The camera notes the arrival time and intensity of each photon of light to build a three dimensional picture of what it can’t actually see. It takes several passes of the scene to build a full picture.
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Is 3D technology the next big wave in video? Or should we skip right ahead to holography? New research is developing ways to stream almost-live video to holographic display, providing a three-dimensional, realistic image without the need for those dorky plastic 3D glasses. And before you ask–yes, this does bring us one step closer to living in a Star Wars world, where holographic princesses deliver desperate pleas for help.

This is the first time researchers [have demonstrated] an optical material that can display “holographic video,” as oppose to static holograms found in credit cards and product packages. The prototype looks like a chunk of acrylic, but it’s actually an exotic material, called a photorefractive polymer, with remarkable holographic properties. [IEEE Spectrum]

The prototype, produced by Nasser Peyghambarian and colleagues at the University of Arizona and Nitto Denko Technical Corporation, displays a holographic image that can be updated every two seconds. This is much better than the four minutes between updates seen in the team’s last prototype, and it gives the audience an almost-real-time representation of what’s happening on the other end of the communication (be it in the other room or across the country). The team expects to continue improving their technology, enabling larger pictures and shorter refresh times.

Hit the break for more details and an additional video…

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The US Missile Defense Agency’s flying laser failed to shoot down a test missile last week. Though in February the same plane successfully destroyed one from 50 miles away, last week’s test at a weapons range off California’s coast was meant to show the Airborne Laser Testbed‘s (ALTB) ability to hit missiles at a 100-mile range.

The laser and jumbo jet combo successfully tracked the missile and hit it, but stopped short of complete destruction, reports AOL News, which broke the story. The agency had not announced the test, which it had rescheduled several times.

“Program officials will conduct an extensive investigation to determine the cause of the failure to destroy the target missile,” the agency said in an e-mailed statement…. [The test], which was designed to demonstrate the weapon’s capability at ranges twice the distance of the initial test, had been delayed at least four times due to various glitches, including problems with the target missile. At one point, the test was scheduled to take place at the opening of a major missile defense conference in Huntsville, Ala., but was delayed due to a software glitch. [AOL News]

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In early 2010, some scientists offered their predictions for the new decade which this blog covered in the post, “Scientists Predict: The 2010s Will Be Freakin’ Awesome–With Lasers.” In what could be an early sign of that sunny prognostication coming true, researchers have announced that they’ve controlled the beating of an embryonic heart with an infrared laser beam. While the work is in its early stages, researchers say this remarkable advance will help them study heart disease and could one day lead to optical pacemakers.  

The embryonic hearts in question came from quail eggs. Each quail embryo was only two or three days old so the heart measured just 2 cubic millimeters in volume; at that stage, the heart is essentially a clump of cells that hasn’t yet developed its four-chambered structure. The pulses of infrared light were delivered by an optical fiber that ended 500 micrometres from the embryo.

Before they switched on the laser, the heart beat once every 1.5 seconds, but firing the laser twice a second quickened the heartbeat to match the laser rate as long as the laser fired…. ”It worked beautifully: the heart rate was in lockstep with the laser pulse rate,” says [study coauthor] Duco Jansen of Vanderbilt University in Nashville, Tennessee. [New Scientist]

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Sure, a laser can shine finely-tuned light to do anything from scanning your barcodes to correcting your vision, but soon that precise hero may meet its match: Physicists have recently imagined a device that can absorb light of certain frequencies, an “anti-laser.”

Absorbing light may not seem all that impressive, since after all, anything that appears black works as an absorber. Your driveway, however, is not the anti-laser. A paper in the Physical Review Letters lays out the plans for this device which can absorb light wave clones (same frequency, phase, and polarization) that some lasers emit. The pickiness of this theoretical light absorber is part of what would make the device unique, just as an important part of what separates a laser from a flashlight is the precision of the light a laser emits.

Instead of amplifying light into coherent pulses, as a laser does, an antilaser absorbs light beams zapped into it. It can be “tuned” to work at specific wavelengths of light, allowing researchers to turn a dial and cause the device to start and then stop absorbing light. “By just tinkering with the phases of the beams, magically it turns ‘black’ in this narrow wavelength range,” says team member A. Douglas Stone, a physicist at Yale University. “It’s an amazing trick.” [Science News]

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When Ikaros unfurled, it unfurled like a spinning top blossoming into a pinwheel. Out in space earlier this month, the center piece of Japan’s solar sail was rotating quickly when it began to extend the arms that had been wrapped up inside. As they stretched out into a stiff X shape, like the stakes that hold a kite taut, the craft slowed to a gentler rotation (a consequence of conservation of angular momentum, like the way a figure skater’s spin slows down when she extends her arms). The JAXA scientists then could let Ikaros stretch the shining sail into a square that spanned 66 feet diagonally.

When Ikaros unfurled, it also breathed new life into a technology that has been dreamed for decades—using the the pressure of sunlight itself to cruise the solar system, and perhaps beyond.

In Brooklyn this week, solar sail enthusiasts gathered for an international symposium. Last night Osamu Mori of the Ikaros team (seen above with a mock-up) was the toast of the party, and a group of experts joined him to celebrate and look forward to a bevy of new explorations. The roster included Planetary Society current director Louis Friedman and director-to-be Bill Nye, NASA’s Les Johnson, Malcolm McDowell of the University of Strathclyde in Scotland, and Roman Kezerashvili of the host New York City College of Technology.

“I feel like they deserve a ticker-tape parade here in New York City,” Friedman said, “rather than just showing up for a scientific conference.”

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It’s not just the sequoias—the towering firs, hemlocks, and other trees of the Pacific Northwest make its forests the tallest in the world, matched only by those in Southeast Asia. That’s according to a study by NASA, which has completed the first survey of the heights of forests throughout the world.

The map, created by NASA’s ICESat, Terra, and Aqua satellites, does more than give bragging rights to West Coast residents. For one thing, it could help scientists who are trying to predict while wildfires might strike, as well as those who want to determine what kind of forests make the best carbon sinks.

The map could also provide a means of monitoring the effects of climate change and deforestation on the world’s forests. Deforestation and land change use is responsible for 20 percent of the world’s emissions, and 48 percent of the world’s deforestation occurs in Brazil, according to a 2008 report by the World Resources Institute [The Independent].

Michael Lefsky and colleagues spent years compiling the data, which they describe in the journal Geophysical Research Letters.

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