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Submission + - Stable Negative Temperature System Created (

slew writes: Scientists at Ludwig Maximilian University of Munich in Germany have created an actual stable system which has an inverted Boltzmann Distribution (aka, Negative Temperature) by using an intermediate bosonic Mott insulator together with a Feshbach resonance in bosonic Potassium with laser cooling.

Although Negative Temperature systems are not uncommon (a pumped laser creates them all the time), they are not usually stable as they are not in thermodynamic equilibrium (in the case of a laser, the high energy state couples to a lower energy state returning the system to a positive temperature realm).

Practical uses are of course far away (they only achieved a billionth of a Kelvin below absolute zero), but studying stable negative temperature systems may help us understand the mechanisms behind dark energy theories.


Submission + - M-Carbon: 50yro mystery solved ( 1

slew writes: Unlike its more famous carbon cousins: diamonds and fullerenes, you've probably never heard of M-Carbon, but this form of compressed graphite which is as hard as diamonds has baffled researcher for half a century. Over the past few years, many theoretical computations have suggested at least a dozen different crystal structures for this phase of carbon, but new experiments showed that only one crystal structure fits the data: M-carbon.

Submission + - the ultimate accessory: iphone case stun-gun (

slew writes: In case you aren't in the loop, this army-reservist came up with this limited edition case for the iphone that doubles as a 650K volt stun-gun. He apparently came up with the idea after being a victim of a home invasion robbery attempt...

Bonus: the stun-gun battery pack can give an extra 20 hours of life to the iPhone if you aren't stunning anyone


Submission + - Scientists capture shadow cast by 1 atom (

slew writes: Scientist at Griffith University have shown the first absorption image of a single atom isolated in a vacuum. A single atomic ion was confined in an RF Paul trap and the absorption imaged at near wavelength resolution with a phase Fresnel lens.

They predict this absorbption imaging technique should prove useful in quantum information processing and using the minimum amount of illumination for bio-imaging of light-sensitive samples.

Here's a pointer to the paper...


Submission + - Uniformed individuals promote democratic consensus in animal groups (

slew writes: Although this isn't "new" research, I just saw this presentation at a GPU Technology Conference keynote. The gist of this research is that a well functioning democracy (a group that is nominally controlled by the numerical majority) seems to require a minimum number of uninfomed or weak-preference individuals to avoid manipulation by a strongly opinionated minority. If this is true, perhaps electing a certain percentage of spin-less clue-less flip-flopping people as legistative representatives instead of all partisan opinionated intransigents is the evolutionary prefered path to take? Nah!

Submission + - photovoltaic powered retinal prosthetic (

slew writes: Although it hasn't been tested on humans yet, stanford researchers have created a new type of retinal prosthetic that is photovoltaic powered. The gist is that external googles convert an image into infrared light and that light conveys both the image and the power for the retinal implant which means no batteries, or bulky induction coils are required for the retinal implant. This should allow for higher resolution implant (the experimental device has 176 pixels where in contrast the currently available retinal implant from SecondSight is about 60 pixels and requires a bulky inductive antenna). Might be a while till we get to a bionic eye, but this should be quite a help for the sight challenged among us.

Submission + - GraphExeter for better solar cells. (

slew writes: Transparent conducting films are a very important part of photoelectric cells and display panels like OLEDS. Unfortunatly, the currently best known material Indium Tin Oxide (aka ITO) is a rare and expensive and much better performing than it's cheaper subsitute (aluminium zinc oxide AZO). Carbon nanotubes thin-films have been considered, but are current limited by sheet resistance. A research group from University of Exeter has created a new Few-Layered graphene (FLG) w/Ferric Chloride "sandwich" which helps to limit the sheet resistance w/o affecting the transparency. If this type of material becomes practical, it could be a good replacement for ITO (which some say economical supplies will run out soon ~2017).

Submission + - electron's 3rd "quasi-particle (aka "orbiton") observed in insulator lattice (

slew writes: Although electrons are usually thought of having 2 properties: spin and charge, bound electrons actually have a 3rd quantum property related to their so-called orbit's angular momentum. Spinon and holon quasi-particles have been observed before which represent the spin and charge quantum values of the electron. Now this experiment takes advantage of the fact that nominally bound electrons can delocalize in a lattice into energy bands and make it possible to measure the effect of the orbiton quasi-particles (which has the value of the electron's angular momentum where it was originally nominally bound, even though now delocalized). Hope that made some sense...

Submission + - Pockets in graphene layers allow viewing of liquids with an electron microscope (

slew writes: Looking at liquids w/ a transmission electron microscope (TEM) to observe things like crystal growth has been difficult to do. This is because liquids need to be confined to a capsule to view them in a TEM (because the electrons are flying at the sample in a chamber near vaccuum pressures where liquids would evaporate or sublimate). Traditional capsules of Silicon Oxide or Silicon Nitride have been fairly opaque. This paper describes a new technique with a "pocket" created between two graphene layers which can hold liquids for observation by a TEM and the graphene is apparently much more transparent than previous materials allowing a better view of the processes (like crystalization), taking place in the liquid. Here's non-paywalled summary article...

Submission + - A new kind of metal theorized to be in the earth's (

slew writes: This article talks about a study accepted to Physical Review Letters that theorizes that Iron oxide goes through an insulator/metal phase change with high temperature and pressure. Originally it was thought to be a crystalline structure change, but now apparently it is theorized to be a new type of metallic state. This discovery might offer new insight on how the earth's magnetic field operates.

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