(Funded by the U.S. Department of Energy)
Scientists from the U.S. Department of Energy’s (DOE) Argonne National Laboratory, SLAC National Accelerator Laboratory, and Lawrence Berkeley National Laboratory; the University of California, Berkeley; Pennsylvania State University; Stanford University; Rice University; the Indian Institute of Science in Bangalore, India; the Japan Synchrotron Radiation Research Institute in Sayo, Japan; RIKEN SPring-8 Center in Sayo, Japan; and the University of Tokyo in Japan are investigating a material with a highly unusual structure – one that changes dramatically when exposed to an ultrafast pulse of light from a laser. At the Center for Nanoscale Materials, a DOE Office of Science user facility at Argonne, the scientists used a technique called transient absorption spectroscopy to detect photocarrier activity within the material. This approach helped them determine how much charge gets released and how quickly the charge decays.

(Funded by the U.S. Department of Energy)
Most optical sensors record data from light and then transmit all of the raw data to a computer for processing. This typically consumes more energy than necessary, because in most applications, only a small amount of information relative to the raw data is needed. So, scientists from the U.S. Department of Energy’s Lawrence Berkeley National Laboratory and Sandia National Laboratories; the University of California, Berkeley; the University of California, Davis; and the University of Texas at Arlington are developing a less power-hungry approach, in which some data processing is conducted in the sensor itself, before the data is sent to a computer or processed by edge computing devices. The new sensor, called a “nanoscale hybrid,” stitches together nanostructures, such as nanotubes and nanowires. It is highly sensitive in part because the sensor’s nanoscale components are smaller than the wavelength of light.

(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.”