Phys.org October 1, 2019 The superconductors known today can only work at very low temperatures and extremely high pressures. As an alternative to metallizing hydrogen, an international team of researchers (China, USA – SUNY Stony Brook) placed a microscopic sample of the metal cerium into a diamond anvil cell, along with a chemical that releases hydrogen and heated with a laser. The cerium sample was squeezed between two flat diamonds to enable the pressure needed for the reaction. As the pressure grew, cerium hydrides with a progressively larger proportion of hydrogen formed in the reactor – CeH2, CeH3, etc. Through […]
Tag Archives: Superconductivity
Scientists predict superelastic properties in a group of iron-based superconductors
Science Daily August 30, 2018 By performing pressure simulations within density functional theory for the family of iron-based superconductors an international team of researchers (Germany, USA – Iowa State University) predicts that in these systems the appearance of two consecutive half-collapsed tetragonal transitions at pressures Pc1and Pc2. They identify clear trends of critical pressures and discuss the relevance of the collapsed phases in connection to magnetism and superconductivity. Not only does this study have implications for properties of magnetism and superconductivity, it may have much wider application in room-temperature elasticity… read more. TECHNICAL ARTICLE
A single photon detection system for the spectrum range up to 2300 nm
Arxiv July 11. 2018 An international team of researchers (Russia, Poland) has demonstrated niobium nitride based superconducting single-photon detectors are sensitive in the spectral range 457 nm – 2300 nm. The system performance was tested in a real-life experiment with correlated photons generated by means of spontaneous parametric down conversion, where one of photon was in the visible range and the other was in the infrared range. They measured a signal to noise ratio as high as 4×104 in their detection setting. A photon detection efficiency as high as 64 % at 1550 nm and 15 % at 2300 nm […]
Electrons slowing down at critical moments
Nanowerk July 7, 2018 An international team of researchers (USA – Argonne National Laboratory, Northwestern University, University of Illinois, Ireland) has shown an unusual slowing down of the recovery of an electronic phase across a first-order phase transition. Following optical excitation, the recovery time of both transient optical reflectivity and X-ray diffraction intensity from the charge-ordered superstructure in a La1/3Sr2/3FeO3 thin film increases by orders of magnitude as the sample temperature approaches the phase transition temperature. In this regime, the recovery time becomes much longer than the lattice cooling time. According to the researchers the abnormal behavior of electrons is […]
Topological insulator ‘flips’ for superconductivity
Science Daily April 30, 2018 Using a novel “flip-chip” technique an international team of researchers (USA – University of Illinois, Japan) prepared single-crystalline Bi2Se3 films with predetermined thicknesses in terms of quintuple layers (QLs) on top of Nb substrates fresh from in situ cleavage. Measurements of the film surface disclosed superconducting gaps and coherence peaks of similar magnitude for both the topological surface states and bulk states and revealed key characteristics relevant to the mechanism of coupling between the topological surface states and the superconducting Nb substrate. This new sample preparation method opens many new avenues in research, building a […]
A different spin on superconductivity—Unusual particle interactions open up new possibilities in exotic materials
Phys.org April 7, 2018 A team of researchers in the US (University of Maryland, Iowa State University, University of Central Florida, Lawrence Berkeley National Laboratory, University of Wisconsin) has uncovered evidence for a new type of superconductivity in the material YPtBi, one that seems to arise from spin-3/2 particles rather than a spin of ½ as in an ordinary superconductor. By varying the temperature while exposing it to weak magnetic field they detected changes to the superconductor’s magnetic properties and found unusual magnetic intrusion. As the material warmed from absolute zero, the field penetration depth for YPtBi increased linearly. According […]
Superconductivity – pairing up with nanotechnology
Nanotechweb February 28, 2018 The factors that determine whether a system will be superconducting and at what temperature remain hard to pin down. However, advances in nanotechnology have given some good pointers where to look, as well as providing promising systems for exploiting superconductivity in real-world applications. Although studies of nanostructures have made huge contributions to advancing understanding of superconductivity, many aspects of the phenomenon remain a marvelous mystery and a great stimulant for further research. Equally as fascinating again is the creativity in applying superconductors in such a diverse array of fields, and here without a doubt the tiny […]