New understanding for superconductivity at high temperaturesJanuary 14, 2008University of Montreal physicist and international team share findings in Science An international research team has discovered that a magnetic field can interact with the electrons in a superconductor in ways never before observed. Andrea D. Bianchi, the lead researcher from the Université de Montréal, explains in the January 11 edition of Science magazine what he discovered in an exceptional compound of metals - a combination of cobalt, indium and a rare earth - that loses its resistance when cooled to just a couple of degrees above absolute zero. "This discovery sharpens our understanding of what, literally, holds the world together and brings physicists one step closer to getting a grip on superconductivity at high temperatures. Until now, physicists were going around in circles, so this discovery will help to drive new understanding," said Prof. Bianchi, who was recruited to UdeM as a Canada Research Chair in Novel Materials for Spintronics last fall and performed his experiments at the Paul Scherrer Institute in Switzerland, in collaboration with scientists from ETH Zurich, the University of Notre Dame, the University of Birmingham, U.K., the Los Alamos National Laboratory and the Brookhaven National Laboratory. Magnetic tornado that grows stronger Using the Swiss Spallation Neutron Source (SINQ), Prof. Bianchi and his team cooled a single-crystal sample of CeCoIn5 down to 50mK above absolute zero and applied a magnetic field nearly high enough to entirely suppress superconductivity. They found that the core of the vortices feature electronic spins that are partly aligned with the magnetic field. This is the first experimental evidence that a theory that describes the properties of superconducting vortices and, for which Abrikosov and Ginzburg received the Nobel Prize in 2003, which does not generally apply in magnetically-induced superconductors. "When subjected to intense magnetic fields, these materials produce a completely new type of magnetic tornado that grows stronger with increasing fields rather than weakening," said Prof. Bianchi. "The beauty of this compound is how we can experiment without breaking it." Superconductors hold great promise for technological applications that will change how modern civilization can store and transmit energy - arguably some of the most pressing challenges today. Other notable applications include superconducting digital filters for high-speed communications, more efficient and reliable generators and motors, and superconducting device applications in medical magnetic resonance imaging machines. The first superconductor was discovered nearly a hundred years ago, and in most materials this curious state with no resistance was shown to arise from the interaction of the electrons with the crystal; however, in this new material, superconductivity is thought to arise from magnetic interactions between electrons. University of Montreal |
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| Related Superconductivity Current Events and Superconductivity News Articles NIST demonstrates 'universal' programmable quantum processor Physicists at the National Institute of Standards and Technology (NIST) have demonstrated the first "universal" programmable quantum information processor able to run any program allowed by quantum mechanics-the rules governing the submicroscopic world-using two quantum bits (qubits) of information. Quantum gas microscope offers glimpse of quirky ultracold atoms Physicists at Harvard University have created a quantum gas microscope that can be used to observe single atoms at temperatures so low the particles follow the rules of quantum mechanics, behaving in bizarre ways. Rutgers physicists discover novel electronic properties in two-dimensional carbon structure Rutgers researchers have discovered novel electronic properties in two-dimensional sheets of carbon atoms called graphene that could one day be the heart of speedy and powerful electronic devices. Putting a Strain on Nanowires Could Yield Colossal Results In finally answering an elusive scientific question, researchers with the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have shown that the selective placement of strain can alter the electronic phase and its spatial arrangement in correlated electron materials. Scientists detect 'fingerprint' of high-temp superconductivity above transition temperature A team of U.S. and Japanese scientists has shown for the first time that the spectroscopic "fingerprint" of high-temperature superconductivity remains intact well above the super chilly temperatures at which these materials carry current with no resistance. Superconductivity: Which one of these is not like the other? Superconductivity appears to rely on very different mechanisms in two varieties of iron-based superconductors. Argonne, UC scientists reach milestone in study of emergent magnetism Scientists at the U.S. Department of Energy's Argonne National Laboratory and the University of Chicago have reached a milestone in the study of emergent magnetism. Thinnest superconducting metal created A superconducting sheet of lead only two atoms thick, the thinnest superconducting metal layer ever created, has been developed by physicists at The University of Texas at Austin. Evidence of macroscopic quantum tunneling detected in nanowires A team of researchers at the University of Illinois has demonstrated that, counter to classical Newtonian mechanics, an entire collection of superconducting electrons in an ultrathin superconducting wire is able to "tunnel" as a pack from a state with a higher electrical current to one with a notably lower current, providing more evidence of the phenomenon of macroscopic quantum tunneling. Multiferroics -- making a switch the electric way Multiferroics are materials in which unique combinations of electric and magnetic properties can simultaneously coexist. More Superconductivity Current Events and Superconductivity News Articles |
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