High-temperature superconductors exhibit a frustratingly varied catalog of odd behavior, such as electrons that arrange themselves into stripes or refuse to arrange themselves symmetrically around atoms. Now two physicists propose that such behaviors, and superconductivity itself, can all be traced to a single starting point, and they explain why there are so many variations.
Scientists in Israel have taken a quantum leap...
Understanding superconductivity has proved to be one of the most persistent problems in modern...
The decades-long effort to create practical superconductors moved a step forward with the...
Semiconductors have had a nice run, but for certain applications, such as astrophysics, they are being edged out by superconductors. Ben Mazin, asst. prof. of physics at the Univ. of California, Santa Barbara, has developed a superconducting detector array that measures the energy of individual photons.
A Binghamton Univ. scientist and his international colleagues report on the successful synthesis of the first superconductor designed entirely on the computer. The synthesized material, a novel iron tetraboride compound, is made out of two common elements, has a brand-new crystal structure and exhibits an unexpected type of superconductivity for a material that contains iron, just as predicted in the original computational study.
A theoretical study conducted by scientists at Japan’s National Institute of Materials Science reveals the possibility of developing a quantum material to transport zero-resistance edge current above room temperature. This capability, allowed by large spin-orbit coupling, will depend on the construction of a new class of topological materials that the researchers have designed.
An international collaboration at Lawrence Berkeley National Laboratory’s Advanced Light Source has induced high-temperature superconductivity in a toplogical insulator, an important step on the road to fault-tolerant quantum computing.
The stage is now set for superconductivity to branch out and meet some of the biggest challenges facing humanity today. This is according to a topical review, published in Superconductor Science and Technology, which explains how superconducting technologies can move out of laboratories and hospitals and address wider issues such as water purification, earthquake monitoring and the reduction of greenhouse gases.
Just like people, materials can sometimes exhibit “multiple personalities.” This kind of unusual behavior in a certain class of materials has compelled researchers at Argonne National Laboratory to take a closer look at the precise mechanisms that govern the relationships between superconductivity and magnetism.
Researchers from the RIKEN Center for Life Science Technologies and Chiba Univ. have developed a high-temperature superconducting wire with an ultrathin polyimide coating only 4 micrometers thick, more than 10 times thinner than the conventional insulation used for high-temperature superconducting wires. The breakthrough should help the development of more compact superconducting coils for medical and scientific devices.
A team led by Oak Ridge National Laboratory’s Amit Goyal, a former R&D Scientist of the Year, has demonstrated that superconducting wires can be tuned to match different operating conditions by introducing small amounts of non-superconducting material, or defects, that influences how the overall material behaves. A wire sample grown with this process exhibited new levels of performance in terms of engineering critical current density.
Scientists at Brookhaven National Laboratory have discovered an unexpected and anomalous pattern in the behavior of one high-performing class of HTS materials. In the new frontier of interface physics, two non-conducting materials can be layered to produce HTS behavior, with tantalizing and mystifying results.
Scientists at Brookhaven National Laboratory and other collaborating institutions have discovered a surprising twist in the magnetic properties of high-temperature superconductors, challenging some of the leading theories. In a new study, scientists found that unexpected magnetic excitations—quantum waves believed by many to regulate HTS—exist in both non-superconducting and superconducting materials.
In the search for understanding how some magnetic materials can be transformed to carry electric current with no energy loss, scientists have used an experimental technique to measure the energy required for electrons to pair up and how that energy varies with direction. The method measures energy levels as small as one ten-thousandth the energy of a single light photon.
The U.S. LHC Accelerator Program (LARP) has successfully tested a powerful superconducting quadrupole magnet that will play a key role in developing a new beam focusing system for CERN’s Large Hadron Collider (LHC). This advanced system, together with other major upgrades to be implemented over the next decade, will allow the LHC to produce 10 times more high-energy collisions than it was originally designed for.
A research team has found superconductivity in the solid form of a compound called carbon disulfide, CS2, which is sometimes used in liquid form as a chemical solvent or insecticide. Superconductivity is usually present in highly ordered molecular structures, but in carbon disulfide, superconductivity arises from a highly disordered state, which is rare. Even more strange is the magnetic state that precedes superconductivity.
Scientists from SLAC National Accelerator Laboratory and Stanford Univ. have used finely tuned x-rays at the Stanford Synchrotron Radiation Lightsource to pin down the source of a mysterious magnetism that appears when two materials are sandwiched together. Why is this mysterious? Neither material shows a hint of magnetism on its own.
In the superconducting state, electrons travel in so-called Cooper pairs through the crystal lattice. An energy gap accounts for the difference in energy needed to break up these pairs into free electrons. In high-temperature superconductors, a similar energy gap also occurs above the superconducting transition temperature: the pseudogap. A German-French research team has constructed a new model that explains how this pseudogap state forms.
Physicists at the U.S. Dept. of Energy's Ames Laboratory have discovered surprising changes in electrical resistivity in iron-based superconductors. The findings offer further evidence that magnetism and superconductivity are closely related in this class of novel superconductors.
Physicists at the University of Arkansas have collaborated with scientists in the United States and Asia to discover that a crucial ingredient of high-temperature superconductivity could be found in an entirely different class of materials. The team found that the way electrons form in superconductive material—known as the Zhang-Rice singlet state—was present in a chemical compound that is very different from conventional superconductors.
Rice University physicists on the hunt for the origins of high-temperature superconductivity have published new findings about a seemingly contradictory state in which a material simultaneously exhibits the conflicting characteristics of both a metallic conductor and an insulator. In this condition, some electrons remain mobile while their neighbors are locked down.
Rice University physicists on the hunt for the origins of high-temperature superconductivity have published new findings this week about a material that becomes “schizophrenic”—simultaneously exhibiting the characteristics of both a metallic conductor and an insulator. In a theoretical analysis in Physical Review Letters, Rice physicists offer an explanation for a strange series of observations described earlier this year by researchers at the Stanford Linear Accelerator Center in Menlo Park, Calif.
In physics, Luttinger’s theorem states that the number of electrons in a material is the same as the number of electrons in all of its atoms added together. But physicists at the University of Illinois and the University of Pennsylvania found that for copper-containing superconductors, known as cuprates, electrons are not enough to carry the current
As one crucial step of achieving controllable quantum devices, physicists at the University of California Santa Barbara have developed an unprecedented level of manipulating light on a superconducting chip. In their experiment, they caught and released photons in and from a superconducting cavity by incorporating a superconducting switch.
A multi-university team of researchers has artificially engineered a unique multilayer material with tailorable properties. It seamlessly alternates between metal and oxide layers, achieving extraordinary superconducting properties such as the ability to transport much more electrical current than non-engineered materials. A superlattice, it is composed of 24 layers that alternate between pnictide superconductor and the oxide strontium titanate.
Researchers in Finland have shown experimentally that vacuum has properties not previously observed. Vacuum contains momentarily appearing and disappearing virtual pairs, which can be converted into detectable light particles. The researchers conducted a mirror experiment to show that by changing the position of the mirror in a vacuum, virtual particles can be transformed into real photons that can be experimentally observed. In a vacuum, there is energy and noise, the existence of which follows the uncertainty principle in quantum mechanics.
Pinning down one of the possible explanations for the phenomenon of high-temperature superconductors—fleeting fluctuations called charge-density waves (CDWs)—could help pave the way for technological advances. Researchers report that they have combined two state-of-the-art experimental techniques to study those electron waves with unprecedented precision in two-dimensional, custom-grown materials.
While the phenomenon of superconductivity has been known for more than a century, the temperature at which it occur has remained too low for any practical applications. The discovery of high-temperature superconductors in the 1980s led to speculation that a surge of new discoveries might quickly lead to room-temperature superconductors. Despite intense research, these materials have remained poorly understood. Until now.
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