Scientists at the U.S. Department of Energy’s (DOE) Argonne National Laboratory have unveiled a new technique that could help advance the development of quantum technology. Their innovation provides an unprecedented look at how quantum materials behave at interfaces. “This technique allows us to study surface phonons — the collective vibrations of atoms at a material’s surface or interface between materials,” said Zhaodong Chu, one of the scientists involved in this study. ​“Our findings reveal striking differences between surface phonons and those in the bulk material, opening new avenues for research and applications.” Some of the research activities were performed at Argonne’s Center for Nanoscale Materials, a DOE Office of Science user facility.

(Funded by the National Institutes of Health)
Scientists at the Icahn School of Medicine at Mount Sinai have developed a lipid nanoparticle system that can deliver messenger RNA (mRNA) to the brain via intravenous injection – a challenge that has long been limited by the protective nature of the blood-brain barrier. The system takes advantage of natural transport mechanisms within the blood-brain barrier that move nanoparticles across the blood-brain barrier. The findings, in mouse models and isolated human brain tissue, show the potential of this system for future treatments for Alzheimer’s disease, amyotrophic lateral sclerosis, brain cancer, and drug addiction.

(Funded by the U.S. Department of Energy)
Researchers from Rice University; the Massachusetts Institute of Technology; Carnegie Mellon University; the National University of Singapore; Southern University of Science and Technology in Shenzhen, China; and Osaka University in Japan have found a two-dimensional (2D) carbon material that is tougher than graphene and resists cracking. Carbon-derived materials, such as graphene, are among the strongest on Earth, but once established, cracks propagate rapidly through them, making them prone to sudden fracture. The new carbon material, called a monolayer amorphous carbon, is both strong and tough. Like graphene, this material is also a 2D material, but unlike graphene, in which atoms are arranged in an ordered lattice, this material incorporates both crystalline and amorphous regions. “This unique design prevents cracks from propagating easily, allowing the material to absorb more energy before breaking,” said Bongki Shin, one of the researchers involved in this study.

(Funded by the U.S. National Science Foundation)
Researchers at North Carolina State University have demonstrated a new technique that uses light to tune the optical properties of quantum dots. The researchers placed green-emitting perovskite quantum dots in a solution containing either chlorine or iodine. The solution was then run through a microfluidic system that incorporated a light source. The microfluidic environment enabled precise reaction control by ensuring uniform light exposure across small solution volumes, approximately 10 microliters per reaction droplet. The light triggered reactions that made the green-emitting perovskite quantum dots move closer to the blue end of the spectrum when chlorine was present in the solvent and closer to the red end of the spectrum when iodine was present in the solvent.

(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.