A team of fusion researchers at the Department of Energy’s Oak Ridge National Laboratory used datasets from measurements on the Joint European Torus, or JET, tokamak to model an improved method for quantifying the amount of plasma-radiated power during a disruption of normal operations.
- Review of Scientific Instruments
Impurities in the plasmas in tokamaks can reduce performance. These impurities are from interactions between the hot plasma and tungsten tokamak walls. This experiment found that tokamak magnetic fields that rotate clockwise direction can remove these impurities. This is the opposite direction from normal and the same direction the plasma current moves.
- Nuclear Materials and Energy
Researchers have discovered a hard-to-observe type of spin called Kardar-Parisi-Zhang (KPZ) in a quantum mechanical system. Their findings demonstrate that KPZ motion accurately describes the changes in time of spin chains—linear channels of spins that interact with one another—in certain quantum materials. This could eventually be harnessed for real-world applications such as heat transport and spintronics.
- Nature Physics
Scientists have synthesized and examined the magnetic fields of tetrafluoride powders of four radioactive elements—thorium, uranium, neptunium, and plutonium. These are actinides, a series of heavy and radioactive elements. This study presents a new way of mapping the distinctive evolution of electronic structure in actinides. This will help researchers develop future nuclear fuels, superconductors, and other materials.
- The Journal of Chemical Physics
To reduce the need for computer power, researchers typically simulate how quarks combine to make up larger particles by simulating quarks heavier than quarks found in nature. Now, using the Summit supercomputer, a team simulated much lighter quarks than possible in the past. This produced more realistic results that will help scientists investigate the Higgs boson.
Scientists have developed a technique called plasmon engineering to create nanomaterials with near-atomic scale control of patterning in silicon. This new research used a specific plasmon engineering method, aberration-corrected electron beam lithography, to control the optical and electronic properties of silicon. This approach could one day be applied to industrial applications.
Scientists demonstrated that ultrathin films of samarium nickel oxide can mask the thermal radiation emitted by hot materials. This is due to the material undergoing a gradual transition from insulator to conductor. This study shows that quantum materials such as samarium nickel oxide can manage thermal radiation with potential applications in infrared camouflage, privacy shielding, and heat transfer control.
Scientists have learned how to place crystalline defects in new materials with atomic-scale precision. This enables materials that can control excitons—energy carriers similar to subatomic particles. New research reveals how to create local energy wells that “capture” the excitons. This small but important step could lead to smaller, more efficient components for optical telecommunications.
- Chemistry of Materials
Researchers have for the first time used a quantum computer to generate accurate results from materials science simulations that can be verified with practical techniques. Eventually, such simulations on quantum computers could be more accurate and complex than simulations on classical digital computers.