(Funded by the U.S. Department of Energy)
An international team led by Rutgers University-New Brunswick researchers has merged two lab-synthesized two-dimensional materials into a synthetic quantum structure once thought impossible to exist and produced an exotic structure expected to provide insights that could lead to new materials at the core of quantum computing. One slice of the quantum structure is made of dysprosium titanate, an inorganic compound used in nuclear reactors, while the other is composed of pyrochlore iridate, a new magnetic semimetal. The specific electronic and magnetic properties of the material developed by the researchers can help in creating very unusual yet stable quantum states, which are essential for quantum computing.

(Funded by the U.S. National Science Foundation and the U.S. Department of Defense)
Engineers at Harvard University have created a bilayer metasurface made of two stacked layers of titanium dioxide nanostructures. Almost a decade ago, the engineers had unveiled the world’s first visible-spectrum metasurfaces – ultra-thin, flat devices patterned with nanostructures that could precisely control the behavior of light and enable applications in imaging systems, augmented reality, and communications. But the single-layer nanostructure design has been in some ways limiting. For example, previous metasurfaces put specific requirements on the manipulation of light’s polarization in order to control the light’s behavior. Using the facilities of the Center for Nanoscale Systems at Harvard, the engineers came up with a fabrication process for freestanding, sturdy structures of two metasurfaces that hold strongly together but do not affect each other chemically.

(Funded by the U.S. Department of Defense)
Rice University researchers have developed an innovative solution to a pressing environmental challenge: removing and destroying per- and polyfluoroalkyl substances (PFAS), commonly called “forever chemicals.” By combining granular activated carbon saturated with PFAS and mineralizing agents like sodium or calcium salts, the researchers applied a high voltage to generate temperatures exceeding 3,000 degrees Celsius in under one second. The intense heat breaks down the strong carbon-fluorine bonds in PFAS, converting them into inert, nontoxic fluoride salts. Simultaneously, the granular activated carbon is upcycled into graphene, a valuable material used in industries ranging from electronics to construction.

(Funded by the U.S. Department of Energy and the U.S. National Science Foundation)
The shape of nanoparticles depends on the choice of solvent and temperature during their growth. But the tiny seed particles that form first and that guide the formation of final nanoparticle shapes are too small to measure accurately. With the help of a supercomputer, Penn State researchers have developed computer simulations to model seed particles with 100 to 200 atoms. They found that the shapes of the tiny particles depend on the solvent composition and temperature in unexpected ways. Surprisingly, in some cases the shape of the seed particle changes dramatically when only a single atom is added or removed.

(Funded by the U.S. National Science Foundation and the National Institute of Standards and Technology)
The fractional quantum Hall effect arises when electrons in two-dimensional materials are subject to a strong perpendicular magnetic field at very low temperatures. Researchers from George Mason University, Brown University, and the National Institute of Standards and Technology have shown that fractional quantum Hall states could be better detected using thermopower measurements than with conventional electrical resistivity. (Thermopower is an electrical voltage generated when charge carriers move from the hot side to the cold side of a conducting or semiconducting material.) The researchers performed thermopower measurements on bilayer graphene and observed new fractional quantum Hall states, which had not been previously reported.