News from the NNI Community - Research Advances Funded by Agencies Participating in the NNI

Researchers from Stanford University and Gyeongsang National University in South Korea have produced soft integrated circuits that convert sensed pressure or temperature to electrical signals, similar to the nerve impulses, to communicate with the brain. The skin-like material consists of three layers, one of which is nitrile, the same rubber that is used in surgical gloves. Integrated in each layer are networks of organic nanostructures that transmit electrical signals, even when stretched. These networks can be engineered to sense pressure, temperature, strain, and chemicals.

Researchers from the City College of New York, the Air Force Research Laboratory, and the Australian National University (Canberra, Australia) have created structured light on a silicon chip and used this added structure to gain new functionalities and control not available before. The scientists created two-dimensional optical metamaterials, or metasurfaces, that hosted a special kind of structured light spinning around just like vortex beams. The researchers also created waveguides for structured light – metal tubes that guide optical signals while preserving the internal structure of light.

Researchers from the National Institute of Standards and Technology, the U.S. Department of Energy’s Idaho National Laboratory, the University of Notre Dame, the University of California Los Angeles, and Indiana University−Purdue University Indianapolis have created a novel 3D printing method that produces materials in ways that conventional manufacturing can’t match. The new process mixes multiple aerosolized nanomaterial inks in a single printing nozzle, varying the ink mixing ratio on the fly during the printing process. This method controls both the printed materials’ 3D architectures and local compositions and produces materials with gradient compositions and properties at microscale spatial resolution.

Physicist Stephen Whitelam, of the Department of Energy’s Lawrence Berkeley National Laboratory, has used neural networks – a type of machine learning model that mimics human brain processes – to train nanosystems to work with greater energy efficiency. Whitelam modeled a so-called “optical trap,” in which laser beams, acting like tweezers of light, can hold and move a nanoscale bead around. He also simulated flipping the state of a nanomagnetic bit between 0 and 1, which is a basic information-erasure/information-copying operation in computing.

Scientists from Brown University, Michigan State University, Columbia University, the U.S. Department of Energy’s Sandia National Laboratories, the University of Innsbruck in Austria, and the National Institute for Materials Science in Japan have described what they believe to be the first measurement showing direct interaction between electrons spinning in a 2D material and photons coming from microwave radiation. The researchers made the measurements on a relatively new 2D material called "magic-angle" twisted bilayer graphene. This graphene-based material is created when two sheets of ultrathin layers of carbon are stacked and twisted to just the right angle.

Northwestern University engineers have developed a new nanoparticle-coated sponge that can remove metals – including toxic heavy metals and critical metals – from contaminated water, leaving safe, drinkable water behind. In proof-of-concept experiments, the researchers tested their new sponge on a highly contaminated sample of tap water, containing more than 1 part per million of lead. With one use, the sponge filtered lead to below detectable levels. The project builds on the team’s previous work to develop highly porous sponges for various aspects of environmental remediation. 

Researchers from Georgia State University and Georgia Institute of Technology have developed a novel type of protein nanoparticle vaccine formulation containing influenza proteins and adjuvant that provided complete protection against influenza viral infections. The protein nanoparticle consists of the influenza nucleoprotein as the core and surface proteins as the coating antigens. The researchers have focused their work on developing different types of protein nanoparticle vaccines against both influenza A and influenza B viral infections.

Engineers at Purdue University have developed a patent-pending tool to make the manufacture of ultrathin semiconductors more consistent, controllable, and repeatable than traditional methods. The tool uses a dry-transfer process to move graphene and other ultrathin, 2D materials from the growth substrate where they are synthesized to a device substrate. Thomas Beechem, an engineer who led the research team said that the tool provides users with more control and degrees of freedom, including creating their own recipes for a scalable process.

Researchers from Columbia University and the City University of New York have developed a new class of integrated photonic devices, called leaky-wave metasurfaces, that can convert light initially confined in an optical waveguide to an arbitrary optical pattern in free space. These devices, which are composed of nano-apertures etched into a polymer layer on top of a silicon nitride thin film, are the first to demonstrate simultaneous control of all four optical degrees of freedom, namely, amplitude, phase, polarization ellipticity, and polarization orientation. Because the devices are so thin, transparent, and compatible with photonic integrated circuits, they can be used to improve optical displays, LIDAR (Light Detection and Ranging), optical communications, and quantum optics.

Researchers from Yale University; the University of Minnesota, Minneapolis; and the U.S. Department of Energy’s Los Alamos National Laboratory have developed and measured a model nanomagnetic array in which the behavior can be best understood as that of a set of wiggling strings. The strings, which are composed of connected points of high energy among the lattice, can stretch and shrink but also reconnect. What makes these strings special is that they are limited to certain endpoints and must connect to those endpoints in particular ways.