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Researchers at the Karlsruhe Institute of Technology set a new record by transmitting 26 terabits of a data per second (“the entire Library of Congress in 10 seconds!” as the usual benchmark goes) using a single laser and a clever FFT and frequency comb technique to split the light into 300+ discrete colors:

The Fourier transform is a well-known mathematical trick that can in essence extract the different colours from an input beam, based solely on the times that the different parts of the beam arrive. The team does this optically - rather than mathematically, which at these data rates would be impossible - by splitting the incoming beam into different paths that arrive at different times, recombining them on a detector. In this way, stringing together all the data in the different colours turns into the simpler problem of organising data that essentially arrive at different times.

Neat.

(Via ACM TechNews)

Mind-boggling stuff like this is why I keep reading science journals. We can already use photons to push and pinch things with their tiny mass (amazing enough), but new research is underway in how to pull with photons:

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.  …  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.

To be filed under “research I like reading about even if I don’t quite understand how it works”, new studies from the University of Oregon into altering and controlling the color of light on the scale of individual photons in fiber optic signalling:

In experiments led by Raymer’s doctoral student Hayden J. McGuinness, researchers used two lasers to create an intense burst of dual-color light, which when focused into the same optical fiber carrying a single photon of a distinct color causes that photon to change to a new color. This occurs through a process known as Bragg scattering, whereby a small amount of energy is exchanged between the laser light and the single photon, causing its color to change. […] 

“In the first study, we worked with one photon at a time with two laser bursts to change the energy and color without using hydrogen molecules,” he said. “In the second study, we took advantage of vibrating molecules inside the fiber interacting with different light beams. This is a way of using one strong laser of a particular color and producing many colors, from blue to green to yellow to red to infrared.”

The laser pulse used was 200 picoseconds long. A picosecond is one-trillionth of a second. Combining the produced light colors in such a fiber could create pulses 200,000 times shorter – a femtosecond (one quadrillionth of a second).

(Via ACM TechNews)

A paper in Optics Express describing a quantum dot-powered “dark pulse” laser. I was totally hoping that this was a device that could emit some kind of anti-light to darken the room, but what they’re really talking about is a laser that can go from light to dark very fast. The on/off pulses are down in the 90-picosecond range, useful for even more precise timekeeping or for new innovations in networking / telecom.

(Via The Register)

Moving things (very, very, very tiny things) using nothing but photons. Not immediately useful given the scale, but this is a first and could have applications in nanoelectromechanics and biology. Originally this same principle was thought to be what powered the nifty Crookes radiometer (that black-and-white vaned vacuum bulb thing that’s now usually sold as a novelty desk toy), but that device is actually moved by thermal transpiration or temperature differences.

(If the above link is behind a paywall for you, you might try the basic Nature writeup instead)

Music of the Large Hadron Collider. From Discover:

Lily Asquith, a physicist searching for the Higgs boson–the elementary particle believed to give everything in the universe mass–is using more than her eyes. With artists and other physicists, she started the LHCsound project to hear subatomic particles.

I’m rarely convinced that audio visualization (what’s the better term for this field?) makes patterns in data easier to find, but it sure can sound interesting.

Nuclear collisions recreate conditions in the universe microsecondsafter the Big Bang. […] We report the observation of antihypertritons — comprised of an antiproton, antineutron, and antilambda hyperon — produced by colliding gold nuclei at high energy. The production and properties of antinuclei, and nuclei containing strange quarks, have implications spanning nuclear/particle physics, astrophysics, and cosmology.

My layman’s understanding of this is that it’s a significant find, if verified. Basically they’ve created a particle that is neither matter nor antimatter, but lies just off the plane of strangeness (“strange” as in the quark), and might be the kind of thing only found at the cores of collapsed stars. The Register’s easy-to-read writeup has a good suggestion that this “negative strangeness” they talk about should be dubbed “hyper-boringness”.

Converting heat energy directly into sound using tiny electrical conductors is a 100-year-old idea for an alternative to the mechanical voice coil wire + moving diaphragm design of traditional speakers, but new research recently submitted to Applied Physics Letters demonstrates a new, actually feasible approach to making these speakers-on-a-chip. Still way too quiet and underpowered for use as a loudspeaker, but might have some novel applications in the near future as research progresses.

I like the name given to the 100 year old invention, though: the thermophone.

NASA plans to send a hot-air-balloon type probe to Saturn’s moon, the only other known body in our solar system to have liquid “seas” on the surface. In order to keep the balloon from crashing into any rocky outcroppings, the team at the JPL has designed an oxygen-burning “rapid buoyancy modulation system” that’s pretty clever:

The lack of any free oxygen in the ice-moon’s air means that the patio gas oceans, clouds etc won’t normally catch fire. Thus NASA’s plan for Titanian hot-air ballooning would reverse the situation on Earth: Rather than burning a stream of patio-gas using oxygen in the air, the moon balloons will burn a stream of oxygen using methane from the surrounding clouds.

A paper in Nature Photonics describing the waveplate mechanism found in the eye of mantis shrimp (stomatopods). These amazing critters can see hyperspectral color ranging from the infrared to the ultraviolet, can perceive different planes of circular polarized light, and have eyes that operate and dart about (saccade) independently. This paper is basically demonstrating that man-made material science has a lot to learn if we want to catch up with nature’s technology.

Personal side question: what are these shrimp on the lookout for that’s led to such a sophisticated eye??

Pioneer of medical instruments, photography, and cinema. Took some very interesting early photographs in his research of animal locomotion and physionomy, which led to his successor Muybridge’s famous collections of plates.