(Funded by the U.S. Department of Defense and the U.S. Department of Energy)
Researchers from Rice University, the University of California Berkeley, the University of Pennsylvania, and the Massachusetts Institute of Technology have shed light on how the extreme miniaturization of thin films affects the behavior of relaxor ferroelectrics — materials with noteworthy energy-conversion properties used in sensors, actuators, and nanoelectronics. The findings reveal that as the films shrink to dimensions comparable to internal polarization structures within the films, their fundamental properties can shift in unexpected ways. More specifically, when the films are shrunk down to a precise range of 25–30 nanometers, their ability to maintain their structure and functionality under varying conditions is significantly enhanced.

(Funded by the U.S. Department of Energy)
Researchers from the U.S. Department of Energy’s Argonne National Laboratory and Fermi National Accelerator Laboratory, as well as Northern Illinois University have discovered that superconducting nanowire photon detectors, which are used for detecting photons (the fundamental particles of light) could potentially also function as highly accurate particle detectors, specifically for high-energy protons used as projectiles in particle accelerators. The ability to detect high-energy protons with superconducting nanowire photon detectors has never been reported before, and this discovery widens the scope of particle detection applications.

(Funded by the U.S. National Science Foundation, the U.S. Department of Defense, and the U.S. Department of Energy)
Physicists from the Massachusetts Institute of Technology, Harvard University, and the National Institute for Materials Science in Tsukuba, Japan, have directly measured superfluid stiffness for the first time in “magic-angle” graphene – materials that are made from two or more atomically thin sheets of graphene twisted with respect to each other at just the right angle. The twisted structure exhibits superconductivity, in which electrons pair up, rather than repelling each other as they do in everyday materials. These so-called Cooper pairs can form a superfluid, with the potential to move through a material as an effortless, friction-free current. “But even though Cooper pairs have no resistance, you have to apply some push, in the form of an electric field, to get the current to move,” says Joel Wang, one of the scientists involved in this study. “Superfluid stiffness refers to how easy it is to get these particles to move, in order to drive superconductivity.”

(Funded by the U.S. Department of Energy and the National Institutes of Health)
Researchers from the University of California, Berkeley; the U.S. Department of Energy’s Lawrence Berkeley National Laboratory; and the University of Cambridge have developed a practical way to make hydrocarbons – molecules made of carbon and hydrogen – powered solely by the sun. The device combines a light absorbing “leaf” made from a high-efficiency solar cell material called perovskite, with a flower-shaped copper nanocatalyst, to convert carbon dioxide into useful molecules. Unlike most metal catalysts, which can only convert carbon dioxide into single-carbon molecules, the copper flowers enable the formation of more complex hydrocarbons with two carbon atoms, such as ethane and ethylene, which are key building blocks for liquid fuels, chemicals, and plastics.

(Funded by the U.S. Department of Energy and the U.S. National Science Foundation)
Researchers from the University of California, Davis, have developed a new technique to trap clusters of platinum atoms in nanoscale islands. Previous work had shown that platinum arranged in clusters of a few atoms on a surface makes a better hydrogenation catalyst than either single platinum atoms or larger nanoparticles of platinum. But such small clusters tend to clump easily into larger particles, losing efficiency. So, the researchers decided to “trap” platinum clusters on a tiny island of cerium oxide supported on a silica surface and noticed that such clusters showed good catalytic activity in hydrogenation of ethylene.