Science Daily April 12, 2022 A key to unlocking new functionalities in quantum materials is the discovery of tunable coupling between spins and other microscopic degrees of freedom. A team of researchers in the US (Pennsylvania State University, University, UC San Diego, Northwestern University SLAC National Accelerator Laboratory, Argonne National Laboratory, Stanford University) has found evidence for interlayer magnetophononic coupling in the layered magnetic topological insulator MnBi2Te4. They observed anomalies in phonon scattering intensities across magnetic field-driven phase transitions, despite the absence of discernible static structural changes. This behavior is a consequence of a magnetophononic wave-mixing process that allows for […]
Category Archives: Quantum materials
New material could be two superconductors in one
MIT News November 15, 2021 An international team of researchers (USA – MIT, Rutgers University, National High Magnetic Field Laboratory, Harvard University, Japan) synthesized layered superconductor Ba6Nb11S28. Instead of via one electron a superconductor carries charge by two electrons bound together in a Cooper pair. By applying an in-plane magnetic field, they observed an abrupt, partial suppression of diamagnetism below the upper critical magnetic field, which is suggestive of an emergent phase within the superconducting state. It turns out this kind of superconductor can be manipulated to form a variety of unusual patterns as Cooper pairs move between Landau levels. […]
Electrical control over designer quantum materials
Science Daily October 22, 2021 Recently engineered stacks of two-dimensional materials have emerged as a powerful platform for studying quantum correlations between electronic states. However, the strength of the interaction between the quantum states is typically fixed once a stack is fabricated. An international team of researchers (Switzerland, Japan) demonstrated that they can induce Feshbach resonance in their system allowing to tune the interaction strength between quantum entities by bringing them into resonance with a bound state. In their case the bounds states were between an exciton in one layer and a hole in the other layer. It turns out […]
Ultrafast control of quantum materials
Phys.org October 18, 2021 An international team of researchers (USA – Brown University, University of Pennsylvania, Germany, Switzerland) reviews recent progress in utilizing ultrafast light-matter interaction to control the macroscopic properties of quantum materials. Particular emphasis is placed on photoinduced phenomena that do not result from ultrafast heating effects but rather emerge from microscopic processes that are inherently nonthermal in nature. Many of these processes can be described as transient modifications to the free energy landscape resulting from the redistribution of quasiparticle populations, the dynamical modification of coupling strengths, and the resonant driving of the crystal lattice. Other pathways result […]
Induced flaws in quantum materials could enhance superconducting properties
Science Daily October 4, 2021 The properties of quantum materials are commonly tuned using experimental variables such as pressure, magnetic field, and doping. An international team of researchers (USA – University of Minnesota, Oak Ridge National Laboratory, Argonne National Laboratory, Croatia, China) has shown that compressive plastic deformation induces low-dimensional superconductivity well above the superconducting transition temperature (Tc) of undeformed SrTiO3, with evidence of possible superconducting correlations at temperatures two orders of magnitude above the bulk Tc. The enhanced superconductivity is correlated with the appearance of self-organized dislocation structures. They observed deformation-induced signatures of quantum-critical ferroelectric fluctuations and inhomogeneous ferroelectric […]
New quantum material discovered
Nanowerk May 26, 2021 Usually, quantum critical behaviour is studied in metals or insulators. But an international team of researchers (USA – Johns Hopkins University, University of Maryland, NIST, Rice University, Austria) looked at a semimetal which is a compound of cerium, ruthenium, and tin – with properties that lie between those of metals and semiconductors. Usually, quantum criticality can only be created under specific environmental conditions however, this semimetal turned out to be quantum critical without any external influences at all. They suspect that it may be because it has a highly correlated electron system where the electrons interact […]
Researchers work to create a roadmap on quantum materials
Phys.org September 25, 2020 Recently the definition of quantum materials has broadened to cover all the materials that allow scientists and engineers to explore emergent quantum phenomena and their potential applications. In this roadmap an international team of researchers (USA – UT Austin, University of Minnesota, Cornell University, France, Germany, South Korea, Canada, Spain, Switzerland, Denmark, the Netherlands, Chile, India, Brazil, Austria) aims to capture a snapshot of the most recent developments in the field, and to identify outstanding challenges and emerging opportunities. The experts in each discipline share their viewpoint and articulate their vision for quantum materials, reflecting the […]
New quantum materials with unique properties
Nanowerk June 23, 2020 Researchers in Germany are working on a German Research Foundation funded project that focuses on novel physical phenomena of solids resulting from a particularly strong coupling between a material’s elastic properties and its electronic quantum phases. Based on the findings obtained, the researchers expect to produce new quantum materials with extraordinary properties and open the application potential resulting from interactions between mechanical and electronic properties…read more.
Observation of non-trivial superconductivity on surface of type II Weyl semimetal
Phys.org February 25, 2020 An international team of researchers (China, USA – University of Tennessee, Israel) reported the experimental evidence for the unconventional superconductivity generated by the surface states in TaIrTe4 from both scanning tunneling microscopy/ spectroscopy (STM/STS) and electrical transport measurements. They demonstrated its superconductivity by both the superconducting gap from STS and the consistent resistance drop from electrical transport. The thickness-independence of ultralow critical current and angular dependence of upper critical field (Bc2) indicate that the superconductivity occurs only in the surface states. The research offers a novel platform for exploring topological superconductors and may contribute to the […]
Perfect quantum portal emerges at exotic interface
Nanowerk June 26, 2019 A team of researchers in the US (University of Maryland, UC Irvine) has observed perfect Andreev reflection in point-contact spectroscopy—a clear signature of Klein tunneling and a manifestation of the underlying ‘relativistic’ physics of a proximity-induced superconducting state in a topological Kondo insulator. The findings shed light on a previously overlooked aspect of topological superconductivity and can serve as the basis for a unique family of spintronic and superconducting devices, the interface transport phenomena of which are completely governed by their helical topological states…read more. TECHNICAL ARTICLE