DC Field Science Highlights
Topology, screws, spin and hedgehogs are words not normally found in the same scientific article but with the discovery of Weyl fermions in thin tellurine films they actually belong together. The work in this highlight describes how Qui et. al. used the unique properties of tellurine and high magnetic fields to identify the existence of Weyl fermions in a semiconductor. This discovery opens a new window into the intriguing world to topological materials.
This research clarifies fundamental relationships between magnetism, superconductivity and the nature of the enigmatic “pseudogap state" in cuprate superconductors. The discovery provides an additional puzzle piece in the theoretical understanding of high-temperature superconductors - a key towards improving and utilizing these materials for technological applications.
Magnetic induction is used in technology to convert an applied magnetic field into an electric current and vice versa. Nature also makes extensive use of this principle at the atomic and molecular level giving scientists a window to observe material properties. Using the 25 T Split-Helix magnet, researchers observed changes in the optical properties of organic materials due to currents induced by applied magnetic fields flowing in molecular rings, evidence that could increase the list of materials that could be used in future magnetic technologies.
Materials with magnetoelectric coupling - a combination of magnetic and electric properties - have potential applications in low-power magnetic sensing, new computational devices and high-frequency electronics. Here, researchers find a new class of magnetoelectric materials controlled by spin state switching.
Topological semimetals are an exciting new area of research due to their number of predicted and unexpected quantum mechanical states. Understanding these materials may also lead to quantum devices that function at near room temperature.
A nematic phase is where the molecular/atomic dynamics show elements of both liquids and solids, like in liquid crystal displays on digital watches or calculators. Using high magnetic fields and high pressure, researchers probed the electronic states of an iron-based superconductor and found that its nematic state weakened superconductivity.
Studies of uranium ditelluride in high magnetic fields show superconductivity switching off at 35 T, but reoccurring at higher magnetic fields between 40 and 65 T.
Research on doped SrCu2(BO3)2 shows anomalies in the magnetization.
In Sr3NiIrO6 vibrations in the crystal lattice (phonons) play an important role in its intriguing magnetic properties that result in a very high coercive field of 55 T. Using a combination of pulsed and DC magnetic fields coupled with magnetization and far-infrared spectroscopy, researchers were able to conclusively link the phonons to the magnetic behavior.
MagLab users have modified the critical current of Nb3SN, a material that was thought to be fully exploited, and boosted its performance by 50%.
The observation of topological states coupled with superconductivity represents an opportunity for scientists to manipulate nontrivial superconducting states via the spin-orbit interaction. While superconductivity has been extensively studied since its discovery in 1910, the advent of topological materials gives scientists a new avenue to explore quantum matter. BiPd is being studied using "MagLab-sized fields" by scientists from LSU in an effort to determine if it is indeed a topological superconductor.
Scientists revealed previously unobserved and unexpected FQH states in monolayer graphene that raise new questions regarding the interaction between electrons in these states.
Scientists found that the emergence of an exotic quantum mechanical phase in Ce1-xNdxCoIn5 is due to a shape change in the Fermi surface. This finding ran counter to theoretical arguments and has led investigators in new directions.
This work provides important insight into one of the parent materials of iron-based superconductors.
In the 14 years since its discovery, graphene has amazed scientists around the world with both the ground-breaking physics and technological potential it displays. Recently, scientists from Penn State University added to graphene's gallery of impressive scientific achievements and constructed a map that will aid future exploration of this material. This work is emblematic of the large number of university-based materials research efforts that use the MagLab to explore the frontiers of science.
Decades ago a mechanism was proposed that described a quantum phase transition to an insulating ground state from a semi-metal (excitonic insulator, or EI) using very similar mechanics to those found in the BCS description of superconductivity. The discovery of this transition to an EI in InAs/GaSb quantum wells is striking not only for the long-sought experimental realization of important physics, but also the presence of recently proposed topological behavior.
Researchers discover that Sr1-yMn1-zSb2 (y,z < 0.1) is a so-called Weyl material that holds great promise for building devices that require far less power.
This finding sheds light on the role of quasiparticle mass enhancement near a quantum critical point in one of the leading families of high-temperature superconductors.
New technique transforms common materials into powerful magnets.
Two independent research teams observed same behavior in double bilayer graphene.