DNA origami enables fabricating superconducting nanowires

Science Daily  January 19, 2021 An international team of researchers (Israel, Germany, USA – Columbia University, Brookhaven National Laboratory) used DNA origami as the platform to build superconducting nanoarchitectures which involves two major components: a circular single-strand DNA as the scaffold, and a mix of complementary short strands acting as staples that determine the shape of the structure. The DNA nanowires were dropcast onto a substrate with a channel and coated with superconducting niobium nitride to convert them into conductive wires. The nanowires were suspended over the channel to isolate them from the substrate during the electrical measurements. Superconducting wires […]

Superconductors are super resilient to magnetic fields

Phys.org  September 7, 2020 It was once assumed that the superconducting-to-normal transition caused by a magnetic field could not be reversed easily. However, it has been known for a long time from experiments that, if you remove the magnetic field, a current-carrying superconductor can, in fact, be returned to its previous state without loss of energy. Researchers in Japan proposed a new explanation for this phenomenon. In the superconducting state, electrons pair up and move in sync, but the true cause of this synchronized motion is due to Berry connection, characterized by the topological quantum number. It is an integer […]

New evidence for quantum fluctuations near a quantum critical point in a superconductor

Phys.org  August 31, 2020 Quantum fluctuations associated with exotic orders may account for the unusual characteristics of the normal state, and possibly affect the superconductivity in Copper oxide high-TC superconductors. Using resonant inelastic X-ray scattering an international team of researchers (SLAC National Accelerator Laboratory, Stanford University, UK) had shown spectroscopic evidence of fluctuations associated with a charge order in nearly optimally doped Bi2Sr2CaCu2O8+δ. In the superconducting state the interplay between charge order fluctuations and bond-stretching phonons increases, an observation that is incompatible with expectations for competing orders. They argue that this behaviour reflects the properties of a dissipative system near […]

An unusual superconductor

Phys.org  September 3, 2020 Researchers in China investigated the superconducting properties of two-dimensional crystalline superconducting PdTe2 films grown by molecular beam epitaxy. They observed the experimental evidence of anomalous metallic state and detected type-II Ising superconductivity existing in centrosymmetric systems. Moreover, the superconductivity of PdTe2 films remains almost the same for more than 20 months without any protection layer. This macro-size ambient-stable superconducting system with strong spin-orbit coupling shows great potentials in superconducting electronic and spintronic applications…read more.

Manipulating atoms to make better superconductors

Science Daily  March 3, 2020 The creation of collective behavior is the fundamental building block from which superconductivity emerges. A team of researchers in the US (University of Illinois at Chicago, SLAC National Accelerator Laboratory, Stanford University) had theoretically predicted in a Kondo droplet, for certain distances between the cobalt atoms, the nanoscopic system should start to exhibit collective behavior, while for other distances, it should not. They confirmed the predictions by experiments that showed that collective behavior appears in Kondo droplets containing as little as 37 cobalt atoms. It allows us to move one step closer to developing the […]

Electronic map reveals ‘rules of the road’ in superconductor

Science Daily  December 6, 2019 An international team of researchers (USA – Rice University, UC Berkeley, SLAC National Accelerator Laboratory, Lawrence Berkeley National Laboratory, Stanford University, China) has developed a band structure map from the data gathered from measurements of a single crystal of iron selenide as it was cooled to the point of superconductivity. They are making observations of different types of exotic materials and figuring out the quantum mechanical rules that govern electron behavior in those materials. The electronic structure helps deciding if a material will be a good conductor or a good insulator or a superconductor…read more. […]

Finding the ‘magic angle’ to create a new superconductor

Science Daily  October 2, 2019 Earlier this year, scientists at MIT reported that graphene could become a superconductor if one piece of graphene were laid on top of another piece and the layers twisted to a specific angle , they called “the magic angle” of between 1 degree and 1.2 degrees. Now an international team of researchers (USA – Ohio State University, TT Dallas, Japan) found that graphene layers still superconducted at a smaller angle, around 0.9 degrees. It is a small distinction, but the findings provide a wealth of new information to help decipher the strongly correlated phenomena observed […]

Making new layered superconductors using high entropy alloys

Science Daily   May 4, 2018 Use of layered materials with a molecular structure consisting of alternating superconducting layers and “blocking layers” acting as insulating spacers is used to design new superconductors that retain superconducting properties at higher temperatures. Researchers in Japan have created new superconductors made of layers of bismuth sulfide and a high entropy rare earth alloy oxyfluoride, containing five rare earth elements – lanthanum, cerium, praseodymium, neodymium, and samarium – at the same crystallographic site. The new material retains superconducting properties over a wider range of lattice parameters than materials without high-entropy-alloy states. The work promises a new […]