Quantcast
Last updated on April 18, 2014 at 16:58 EDT

Latest Physical Review Letters Stories

2011-11-15 09:45:27

Study offers new explanation of conduction at interface of oxide materials To improve the electronic devices that keep our modern, hyper-connected world organized, scientists are on the hunt for new semiconductor materials, which control the flow of electricity that powers smart phones and other electronic devices. One answer could lie with an unusual form of electrical conductivity that takes place at the junction of two oxides, materials made of oxygen and metal. When an oxide made up...

Image 1 - Bats Can Change Ear Shape To Make Their Hearing More Flexible
2011-11-15 05:24:09

"Certain bats can deform the shapes of their ears in a way that changes the animal's ultrasonic hearing pattern. Within just one tenth of a second, these bats are able to change their outer ear shapes from one extreme configuration to another," said Rolf Müller, associate professor of mechanical engineering at Virginia Tech. Müller and his students wrote a paper on their work that is appearing this week in Physical Review Letters, a prestigious peer-reviewed...

2011-11-09 10:36:17

A new type of active metamaterial that incorporates semiconductor devices into conventional metamaterial structures is demonstrating an ability to have power gain while retaining its negative refraction property, a first in the world of metamaterials research. "Our simulation and experimental results show that the addition of the battery powered semiconductor diodes not only provided gain, but also maintained the negative index of this kind of metamaterial," said Dr. Hao Xin of the...

2011-11-07 17:01:09

Caltech Engineers Reveal How Scandium Trifluoride Contracts with Heat They shrink when you heat 'em. Most materials expand when heated, but a few contract. Now engineers at the California Institute of Technology (Caltech) have figured out how one of these curious materials, scandium trifluoride (ScF3), does the trick–a finding, they say, that will lead to a deeper understanding of all kinds of materials. The researchers, led by graduate student Chen Li, published their results in...

2011-10-13 09:40:18

A simple atomic nucleus could reveal properties associated with the mysterious phenomenon known as time reversal and lead to an explanation for one of the greatest mysteries of physics: the imbalance of matter and antimatter in the universe. The physics world was rocked recently by the news that a class of subatomic particles known as neutrinos may have broken the speed of light. Adding to the rash of new ideas, University of Arizona theoretical physicist Bira van Kolck recently...

2011-10-11 10:07:42

A coupled line of swinging pendulums apparently has nothing in common with an elastic film that buckles and folds under compression while floating on a liquid, but scientists at the University of Chicago and Tel Aviv University have discovered a deep connection between the two phenomena. Energy carried in ordinary waves, like those seen on the ocean near a beach, quickly disperses. But the energy in the coupled pendulums and in compressed elastic film concentrates into different kinds of...

2011-10-03 12:32:49

Molecular motion in proteins comes in three distinct classes, according to a collaboration by researchers at the Department of Energy's Oak Ridge National Laboratory and the University of Tennessee, in research reported in Physical Review Letters. The research team, directed by ORNL-UT Governor's Chairs Jeremy Smith and Alexei Sokolov, combined high-performance computer simulation with neutron scattering experiments to understand atomic-level motions that underpin the operations of...

2011-09-15 12:22:34

Berkeley Lab scientists uncover the secret of remarkable photovoltages in ferroelectrics If solar cells could generate higher voltages when sunlight falls on them, they'd produce more electrical power more efficiently. For over half a century scientists have known that ferroelectrics, materials whose atomic structure allows them to have an overall electrical polarization, can develop very high photovoltages under illumination. Until now, no one has figured out exactly how this photovoltaic...

Image 1 - New Record For Measurement Of Atomic Lifetime
2011-09-08 05:40:30

  Researchers at the Niels Bohr Institute have measured the lifetime of an extremely stable energy level of magnesium atoms with great precision. Magnesium atoms are used in research with ultra-precise atomic clocks. The new measurements show a lifetime of 2050 seconds, which corresponds to approximately ½ hour. This is the longest lifetime ever measured in a laboratory. The results have been published in the scientific journal Physical Review Letters. The experiment...

2011-08-31 23:38:08

In solid materials with regular atomic structures, figuring out weak points where the material will break under stress is relatively easy. But for disordered solids, like glass or sand, their disordered nature makes such predictions much more daunting tasks. Now, a collaboration combining a theoretical model with a first-of-its kind experiment has demonstrated a novel method for identifying “soft spots” in such materials. The findings from University of Pennsylvania and...