Physicists find new order in quantum electronic material

Jan 30, 2013

Two Rutgers physics professors have proposed an explanation for a new type of order, or symmetry, in an exotic material made with uranium – a theory that may one day lead to enhanced computer displays and data storage systems and more powerful superconducting magnets for medical imaging and levitating high-speed trains.

Their discovery, published in this week's issue of the journal Nature, has piqued the interest of scientists worldwide. It is one of the rare theory-only papers that this selective publication accepts. Typically the journal's papers describe results of laboratory experimentation.

Collaborating with the Rutgers professors was a at Massachusetts Institute of Technology (MIT) who earned her doctorate at Rutgers.

"Scientists have seen this behavior for 25 years, but it has eluded explanation." said Piers Coleman, professor in the Department of Physics and Astronomy in the School of Arts and Sciences. When cooled to 17.5 degrees above absolute zero or lower (a bone-chilling minus 428 degrees Fahrenheit), the flow of electricity through this material changes subtly.

The material essentially acts like an electronic version of polarized sunglasses, he explains. Electrons behave like , and normally these magnets can point in any direction. But when they flow through this cooled material, they come out with their magnetic fields aligned with the material's main crystal axis.

This effect, claims Coleman, comes from a new type of hidden order, or symmetry, in this material's magnetic and . Changes in order are what make liquid crystals, and superconductors work and perform useful functions.

"Our quest to understand new types of order is a vital part of understanding how materials can be developed to benefit the world around us," he said.

Similar discoveries have led to technologies such as , which are now ubiquitous in flat-screen TVs, computers and smart phones, although the scientists are quick to acknowledge that their theoretical discovery won't transform high-tech products overnight.

Coleman, along with Rutgers colleague Premala Chandra and MIT collaborator Rebecca Flint, describe what they call a "hidden order" in this compound of uranium, ruthenium and silicon. Uranium is commonly known for being nuclear reactor fuel or weapons material, but in this case physicists value it as a heavy metal with electrons that behave differently than those in common metals.

Recent experiments on the material at the National High Magnetic Field Laboratory at Los Alamos National Laboratory in New Mexico provided the three physicists with data to refine their discovery.

"We've dubbed our fundamental new order 'hastatic' order, named after the Greek word for spear," said Chandra, also a professor in the Department of Physics and Astronomy. The name reflects the highly ordered properties of the material and its effect on aligning electrons that flow through it.

"This new category of order may open the world to new kinds of materials, magnets, superconductors and states of matter with properties yet unknown," she said. The scientists have predicted other instances where hastatic order may show up, and physicists are beginning to test for it.

Explore further: How the physics of champagne bubbles may help address the world's future energy needs

More information: Research paper: www.nature.com/nature/journal/… ull/nature11820.html
News and Views article: www.nature.com/nature/journal/… 34/full/493619a.html

Related Stories

Stripes offer clues to superconductivity

May 17, 2010

New images of iron-based superconductors are providing telltale clues to the origin of superconductivity in a class of ceramic materials known as pnictides. The images reveal that electrons responsible for ...

Physicists discover surprising variation in superconductors

Jan 28, 2009

(PhysOrg.com) -- MIT physicists have discovered that several high-temperature superconductors display patchwork quilt-like variations at the atomic scale, a surprising finding that could help scientists understand a new class ...

Recommended for you

User comments : 8

Adjust slider to filter visible comments by rank

Display comments: newest first

Tektrix
4 / 5 (4) Jan 30, 2013
Egleton
2.3 / 5 (6) Jan 30, 2013
"Typically the journal's papers describe results of laboratory experimentation."
Except that they don't. They only publish experiments that reinforce their models.
If the empirical results don't correspond to their interpretation of reality they are routinely rejected.
They will not publish any of the thousands of experiments that have been done over the last 30 years on Cold Fusion.

One might be tempted to follow the money. Who benefits? Oil, the Petro-Dollar and the reserve status of the $US if oil energy becomes obsolete.etc.
http://lenr-canr..../?p=1373
http://lenr-canr...._id=1127
Foundation
1 / 5 (1) Jan 31, 2013
When did Scientific American become a scientific journal like Nature, Egleton?
katesisco
2 / 5 (3) Jan 31, 2013
Well, this claims that the theory is not supported but 5/2012 research from Germany shows this effect. When ions get closer.
I suspect this is how bh(LT starbodys) amass their gas. And since science admits bh degrade, it follows that a mass or some other trigger initiates a phase change and the quantum density goes from very dense and hot to very cold and spaced. This is what is now happening to the MW nucleus. It is bleeding cold and spaced gas.
katesisco
2.5 / 5 (2) Jan 31, 2013
More info: http://phys.org/n...tml#nRlv
says rutgers group used ytterbium to produce on/off/idle aspect.
ValeriaT
3 / 5 (2) Jan 31, 2013
I could explain, what this article is about, but it needs some imagination, as I've no animated pictures prepared. In contemporary solid phase physics a two kinds of materials were profiled: the light and heavy fermion materials.
The electrons within light fermion materials do behave like the fluid inside of hydrophobic sponge. Most of electron fluid will be expelled from its pores into cavities, where it forms compact droplets, where the electrons are compressed mutually (Wigner orbitals). The charge is moving there in longitudinal waves with very high speed - the extreme case of light fermion materials are superconductors, where portion of electrons becomes massless in this way.

But we can have the opposite situation of material, where the electron fluid is attracted to atoms instead. The electrons are sucked into pores (spaces between atoms) there and low number of electrons remains between atoms. The electrons are moving in transverse waves preferably inside of such materials.
ValeriaT
2.5 / 5 (2) Jan 31, 2013
Why these materials are called "heavy fermion" materials? You may imagine the transport of electrons within such a materials like the traveling of suite of feared tyrant across densely populous medieval city, which is crossed with dense mesh of narrow streets. Because the people fear of tyrant, his motion across city is followed with perpendicular motion of many other people, who are escaping before him into perpendicular streets and who are doing place for tyrant in this way. When the tyrant passes by, most of these people are returning back from perpendicular streets into main street again.

It means, inside of heavy fermion material every motion of single conductive electron is connected with simultaneous back and forth motion of many other electrons in perpendicular direction, which are just doing space for conductive electrons. Their motion has a large inertia and it's slowing the propagation of conductive electrons in this way. It's opposite effect to superconductivity.
ValeriaT
2.5 / 5 (2) Jan 31, 2013
With respect to conduction theory it's significant, the motion of electrons in perpendicular direction prohibits the charge transport, but it's the source of hidden magnetic field and eddy currents, which are following it. Actually the motion of electrons through heavy fermion materials is pretty similar to motion of magnet around highly conductive material - the magnets gets braked with eddy currents inside of material in invisible way. The electrons involved are doing a circular motion, which is quite similar to the motion of particles inside of transverse waves at the water surface. The electrons moving in circles are doing magnetic field and this magnetic field orients the paramagnetic atoms with unpaired electrons within the material.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.