(Funded by the U.S. Department of Defense, the U.S. Department of Energy, and the U.S. National Science Foundation)
Researchers from the Massachusetts Institute of Technology, Purdue University, Stanford University, Rice University, and the U.S. Department of Energy’s Lawrence Berkeley National Laboratory, Argonne National Laboratory, and Oak Ridge National Laboratory have described how a type of quasiparticle, called a polaron, behaves in tellurene, a nanomaterial made up of tiny chains of tellurium atoms. A polaron forms when charge-carrying particles such as electrons interact with vibrations in the atomic or molecular lattice of a material. The researchers had hypothesized that as tellurene transitions from bulk to nanometer thickness, polarons change from large, spread-out electron-vibration interactions to smaller, localized interactions. Computations and experimental measurements backed up this scenario.

(Funded by the U.S. National Science Foundation and the National Institutes of Health)
Researchers from Georgia Tech and the University of California Riverside have developed biosensors made of iron oxide nanoparticles and special molecules called cyclic peptides that recognize tumor cells better than current biosensors. The cyclic peptides respond only when they encounter two specific types of enzymes – one secreted by the immune system, the other by cancer cells. In animal studies, the biosensors distinguished between tumors that responded to a common cancer treatment that enhances the immune system from tumors that resisted treatment.

(Funded by the U.S. National Science Foundation)
Researchers from Carnegie Mellon University have found a way to control the size and structure of active colloids while yielding more than 100 times the amount created by earlier fabrication methods. The team’s active colloids are linked together using DNA nanostructures – an innovation that makes them flexible, agile, and responsive to signals in their environment. Typically, DNA nanotechnology can only be studied using expensive equipment. In this case, because the DNA is attached to the colloid particles, researchers can observe any nanoscale phenomenon – such as the DNA structures changing shape – in real time by observing changes in the colloid’s movement under a microscope.

(Funded by the U.S. National Science Foundation)
Researchers from Stanford University; the IBM T.J. Watson Research Center in Yorktown Heights, NY; the Korea Electronics Technology Institute in Seongnam-si, South Korea; and Ajou University in Suwon, South Korea, have shown that niobium phosphide can conduct electricity better than copper in films that are only a few atoms thick. Many researchers have been working to find better conductors for nanoscale electronics, but so far the best candidates have had extremely precise crystalline structures, which need to be formed at very high temperatures. The niobium phosphide films made in this study are the first examples of non-crystalline materials that become better conductors as they get thinner, and they can be created at lower temperatures.

(Funded by the U.S. Department of Energy, the U.S. Department of Defense, and the U.S. National Science Foundation)
Scientists from Oregon State University; the Molecular Foundry at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory; Columbia University; and the Autonomous University of Madrid, Spain, have discovered luminescent nanocrystals that can be quickly toggled from light to dark and back again. “Normally, luminescent materials give off light when they are excited by a laser and remain dark when they are not,” said Artiom Skripka, one of the scientists involved in this study. “In contrast, we were surprised to find that our nanocrystals live parallel lives. Under certain conditions, they show a peculiar behavior: They can be either bright or dark under exactly the same laser excitation wavelength and power.”