Other materials stories that may be of interestPublished on April 9th, 2012 | By: Peter Wray
Something should be of interest here:
(USC News) Diamonds are forever – or, at least, the effects of this diamond on quantum computing may be. A team that includes scientists from USC has built a quantum computer in a diamond, the first of its kind to include protection against “decoherence” – noise that prevents the computer from functioning properly. Like all diamonds, the diamond used by the researchers has impurities – things other than carbon. The more impurities in a diamond, the less attractive it is as a piece of jewelry because it makes the crystal appear cloudy. The team, however, utilized the impurities themselves. A rogue nitrogen nucleus became the first qubit. In a second flaw sat an electron, which became the second qubit. (Though put more accurately, the “spin” of each of these subatomic particles was used as the qubit.)
(Detroit News) US manufacturers are now more than 40 percent dependent on imports of many commodity and rare earth metals.For example, import reliance on gallium is at 94 percent, cobalt and titanium 81 percent, chromium 56 percent, silicon 44 percent and nickel 43 percent. These minerals are critical for defense and energy technologies and many high-tech consumer products. Consider nickel, which is needed in the manufacture of stainless steel and electricity storage batteries, among other things. Oregon has the only US mine producing nickel. Almost all of the domestic nickel comes from recycling alloys containing nickel. Now, thanks to a $100-million-plus investment by Rio Tinto, the Eagle nickel mine in Michigan’s Upper Peninsula is expected to open in 2014, producing 16,000 tons of nickel and 10,000 tons of copper.
(PNAS) Here we demonstrate a scalable method for creating extremely small structures in graphene with atomic precision. It consists of inducing defect nucleation centers with energetic ions, followed by edge-selective electron recoil sputtering. As a first application, we create graphene nanopores with radii as small as 3 Å, which corresponds to 10 atoms removed. We observe carbon atom removal from the nanopore edge in situ using an aberration-corrected electron microscope, measure the cross-section for the process, and obtain a mean edge atom displacement energy of 14.1 ± 0.1 eV. This approach does not require focused beams and allows scalable production of single nanopores and arrays of monodisperse nanopores for atomic-scale selectively permeable membranes.
(Science) Some physicists argue that phonons must still play a key indirect role in high-temperature superconductors. And experiments have shown that the phonons and electrons do interact in the compounds. Now, Claudio Giannetti of the Catholic University of the Sacred Heart in Brescia, Italy, and a dozen colleagues report data that, they say, show that electrons alone tell the whole story. They shined pulses of laser light onto a high-temperature superconductor called bismuth strontium calcium yttrium copper oxide (BSCCO) to study how the material reflects light at various wavelengths,
(PNAS) We show that in the stoichiometry CaH6 a body-centered cubic structure with hydrogen that forms unusual “sodalite” cages containing enclathrated Ca stabilizes above pressure 150 GPa. The stability of this structure is derived from the acceptance by two H2 of electrons donated by Ca forming an “H4” unit as the building block in the construction of the three-dimensional sodalite cage. This unique structure has a partial occupation of the degenerated orbitals at the zone center. The resultant dynamic Jahn-Teller effect helps to enhance electron-phonon coupling and leads to superconductivity of CaH6. A superconducting critical temperature (Tc) of 220-235 K at 150 GPa obtained from the solution of the Eliashberg equations is the highest among all hydrides studied thus far.
(MIT Technology Review) If Germany is to meet its ambitious goals of getting a third of its electricity from renewable energy by 2020 and 80 percent by 2050, it must find a way to store huge quantities of electricity in order to make up for the intermittency of renewable energy. Siemens says it has just the technology: electrolyzer plants, each the size of a large warehouse, that split water to make hydrogen gas. The hydrogen could be used when the wind isn’t blowing to generate electricity in gas-fired power plants, or it could be used to fuel cars. Unlike conventional industrial electrolyzers, which need a fairly steady supply of power to efficiently split water, Siemens’s new design is flexible enough to run on intermittent power from wind turbines.
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