A research team led by a Brown Univ. physicist has produced new evidence for an exotic superconducting state, first predicted a half-century ago, that can arise when a superconductor is exposed to a strong magnetic field. This new understanding of what happens when electron spin populations become unequal could have implications beyond superconductivity.
Research by an international team of scientists has uncovered a new, unpredicted behavior in a...
Computer chips with superconducting circuits would be 50 to 100 times as energy efficient as...
Imagine being able to tune the properties of a solid material just by flashing pulses of light on it. That is one potential payoff of electrons and atoms interacting with ultrashort pulses of light. The technology of ultrafast spectroscopy is a key to understanding this phenomenon and now a new wrinkle to that technology, observations of electron self-energy, has been introduced by Lawrence Berkeley National Laboratory researchers.
A new frontier for studying 2-D matter is provided by planar collections of electrons at the surface of transition-metal-oxide (TMO) materials, in which high electron densities give rise to interactions that are stronger than in semiconductors. Scientists hope to find exotic phenomena in these highly-interactive electron environments and one of the leaders in this effort is James Williams, a new fellow at the Joint Quantum Institute.
Research from North Carolina State Univ. shows that a type of modified titania, or titanium dioxide, holds promise as an electrical insulator for superconducting magnets, allowing heat to dissipate while preserving the electrical paths along which current flows. Superconducting magnets are being investigated for use in next-generation power generating technologies and medical devices.
Physicists studying the effects of embedding magnetic spins onto the surface of a superconductor recently report that the spins can interact differently than previously thought. This hybrid platform could be useful for quantum simulations of complex spin systems, having the special feature that the interactions may be controllable, something quite unusual for most condensed matter systems.
New measurements of atomic-scale magnetic behavior in iron-based superconductors by researchers at Oak Ridge National Laboratory and Vanderbilt Univ. are challenging conventional wisdom about superconductivity and magnetism. The study provides experimental evidence that local magnetic fluctuations can influence the performance of iron-based superconductors, which transmit electric current without resistance at relatively high temperatures.
Thanks to a $1.5 million innovation award from the Gordon and Betty Moore Foundation, Rice Univ. physicist Emilia Morosan is embarking on a five-year quest to cook up a few unique compounds that have never been synthesized or explored. Morosan is no ordinary cook; her pantry includes metals, oxides and sulfides, and her recipes produce superconductors and exotic magnets.
The search for zero-resistance conductors that can operate at realistic temperatures has been frustrated by the inability to understand high-temperature superconductors, particularly their magnetic structure. Researchers have done this at the atomic scale for the first time with a so-called strongly correlated electron system of iron telluride. Previously, magnetic information was provided by neutron diffraction, which is imprecise.
Physicists have identified the “quantum glue” that underlies a promising type of superconductivity—a crucial step towards the creation of energy superhighways that conduct electricity without current loss. The research, published online in the Proceedings of the National Academy of Sciences, is a collaboration between the Univ. of Illinois at Chicago, Cornell Univ. and Brookhaven National Laboratory.
Using a new type of large-scale magnet conductor, scientists in Japan have recently achieved an electrical current of 100,000 A, a world record. The conductor, which was built using yttrium-based high-temperature superconducting tapes for high mechanical strength, is a prototype for using in a future fusion reactor.
When a superconductor is exposed to a magnetic field, a surface current creates a magnetic field that cancels the field inside the superconductor. This phenomenon, known as the Meissner-Ochsenfeld effect, was first observed in 1933. In a research first, scientists have succeeded in measuring an analogue of the Meissner effect in an optical crystal with ultracold atoms. This validates theoretical predictions dating back more than 20 years.
Using a scanning tunneling microscope to visualize the electronic structure of the oxygen sites within a superconductor, a Binghamton Univ. physicist and his colleagues say they have unlocked one key mystery surrounding high-temperature superconductivity. The team found a density wave with a d-orbital structure, which is a pattern new to this type of superconductor and they may be found in all cuprates.
For his doctoral dissertation, Yu Chen developed a novel way to fabricate superconducting nanocircuitry. However, the extremely small zinc nanowires he designed did some unexpected things, including demonstrating dissipation characteristics though only to be present in normal states. After long and careful work, which involved both experimental and theoretical efforts, researchers have found an explanation that fits.
An international research team led by scientists in Barcelona has developed a material which guides and transports a magnetic field from one location to the other, similar to how an optical fiber transports light or a hose transports water. The magnetic hose consists of a ferromagnetic cylinder covered by a superconductor material, a surprisingly simple design made possible by complicated theoretical calculations and experimentation.
A breakthrough has been made in identifying the origin of superconductivity in high-temperature superconductors, which has puzzled researchers for the past three decades. Researchers in the U.K. have found that ripples of electrons, known as charge density waves or charge order, create twisted ‘pockets’ of electrons in these materials, from which superconductivity emerges.
Quantum criticality, the strange electronic state that may be intimately related to high-temperature superconductivity, is notoriously difficult to study. But a new discovery of “quantum critical points” could allow physicists to develop a classification scheme for quantum criticality—the first step toward a broader explanation.
Quantum criticality, the strange electronic state that may be intimately related to high-temperature superconductivity, is notoriously difficult to study. But a new discovery of “quantum critical points” could allow physicists to develop a classification scheme for quantum criticality, the first step toward a broader explanation.
An international team of researchers from the USA and Japan, including Takao Sasagawa at Tokyo Institute of Technology, have uncovered a two-stage transition in lanthanum-strontium-copper-oxide high-temperature superconductors (LSCOs), leading to the first complex phase diagram of the behavior of LSCOs. This research could improve understanding of high-temperature superconductivity under magnetic fields.
Scientists at the U.S. Dept. of Energy’s Argonne National Laboratory have discovered a previously unknown phase in a class of superconductors called iron arsenides. This sheds light on a debate over the interactions between atoms and electrons that are responsible for their unusual superconductivity.
For the first time, scientists have a clearer understanding of how to control the appearance of a superconducting phase in a material, adding crucial fundamental knowledge and perhaps setting the stage for advances in the field of superconductivity. The paper focuses on a calcium-iron-arsenide single crystal, which has structural, thermodynamic and transport properties that can be varied through carefully controlled synthesis.
A fully functional quantum computer is one of the holy grails of physics. Unlike conventional computers, the quantum version uses qubits (quantum bits), which make direct use of the multiple states of quantum phenomena. When realized, a quantum computer will be millions of times more powerful at certain computations than today’s supercomputers.
Research from North Carolina State Univ. finds that impurities can hurt performance, or possibly provide benefits, in a key superconductive material that is expected to find use in a host of applications, including future particle colliders. The size of the impurities determines whether they help or hinder the material’s performance.
Scientists at Yale Univ. have confirmed a 50-year-old, previously untested theoretical prediction in physics and improved the energy storage time of a quantum switch by several orders of magnitude. High-quality quantum switches are essential for the development of quantum computers and the quantum Internet.
Carefully timed pairs of laser pulses at the Linac Coherent Light Source have been used to trigger superconductivity in a promising copper-oxide material and immediately take x-ray snapshots of its atomic and electronic structure as superconductivity emerged. The results of this effort have pinned down a major factor behind the appearance of superconductivity, and it hinges around “stripes” of increase electrical charge.
For more than a quarter of a century, high-temperature superconductors have perplexed scientists who seek to understand the physical phenomena responsible for their unique properties. Thanks to a new study by Argonne National Laboratory, researchers have identified and solved at least one paradox in the behavior of high-temperature superconductors.
An international team of scientists has reported the first experimental observation of the quantum critical point (QCP) in the extensively studied “unconventional superconductor” TiSe2, finding that it does not reside as predicted within the superconducting dome of the phase diagram, but rather at a full GPa higher in pressure.
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