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

Scientists from the University of Texas at Dallas, the University of Gottingen, and Ludwig Maximilian University of Munich have demonstrated the quantization of electrical resistance using two-layer graphene. The quantization effect occurs when the resistance adopts a fixed value that is independent of the basic material. The extremely clean double layers of graphene show this effect at low temperatures and at almost undetectable magnetic fields, with implications for the development of innovative computer components and data storage.

MIT physicists report on a new approach to achieving Bloch oscillations in graphene superlattices. Normally, electrons exposed to a constant electric field accelerate in a straight line, but electrons in a crystal can behave differently. Upon exposure to an electric field, they can oscillate in tiny waves, called Bloch oscillations. Bloch oscillations occur at a frequency value that is the same for all electrons and is tunable by the applied electric field.

Researchers at North Carolina State University have utilized two-dimensional hybrid metal halides in a device that allows directional control of terahertz radiation generated by a spintronic scheme. The device has better signal efficiency than conventional terahertz generators and is thinner, lighter, and less expensive to produce. This work could be a first step in exploring the use of 2D hybrid metal halide materials in other spintronic applications.

The National Science Foundation has awarded 31.5 million for 22 new research and seed projects – half of which are related to nanotechnology – through its Future Manufacturing Program. These awards will allow scientists and engineers to advance research in the emerging areas of biomanufacturing, cyber manufacturing and eco manufacturing.

An international group of researchers has recently devised a new strategy to create graphene nanoribbons with smooth edges that are below 10 nanometers in width. This method is based on the use of squashed carbon nanotubes. Graphene nanoribbons that have smooth edges, a sizable bandgap, and high charge carrier mobility could be highly valuable for electronic and optoelectronic applications.

Physicists at the University of Colorado Boulder have addressed the question: Why do some ultra-small heat sources cool down faster if you pack them closer together? They used computer-based simulations to track the passage of heat from nano-sized silicon bars and discovered that when they placed the heat sources close together, the vibrations of energy they produced began to bounce off each other, scattering heat away and cooling the bars down.

Scientists at the University of Michigan have developed a new way to help patients benefit from the most common form of immunotherapy, called immune checkpoint inhibitors, by using new and safe molecules called agonists to augment the body's immune response. When researchers added manganese ions to STING agonists (STING is a protein essential to the immune response against infection, as well as cancer), the manganese ions and STING proteins formed nano-sized crystals. These nano-sized crystals significantly increased cellular uptake of STING agonists and STING activation by immune cells. This study is the first time that nanoparticles delivering STING agonists and metal ions have been developed for intravenous cancer immunotherapy, which could open new doors for cancer immunotherapy treatments.

Researchers from the University at Buffalo have developed a new treatment that uses reverse vaccination to pre-expose the body to medications and build immune tolerance. The nanoparticle-based treatment could be applied to a broad range of drug therapies, autoimmune disorders, and allergies. The treatment was effective when delivered both intravenously and orally.

Scientists at the University of Chicago have invented a thermal insulator that can funnel heat around at the microscopic level. They stacked ultra-thin layers of crystalline sheets on top of each other but rotated each layer slightly, creating a material with atoms that are aligned in one direction but not in the other. The result is a material that is extremely good at both containing heat and moving it, albeit in different directions – an unusual ability that could have very useful applications in electronics.

Researchers at the University of Texas at Austin have solved a common issue with medical sensing technology: slight changes in pressure can throw wearable pressure sensors off track. Their solution is an innovative, first-ever, hybrid sensing approach that allows the device to possess properties of the two predominant types of sensors in use today, piezo-capacitive and piezo-resistive. They utilized an electrically conductive and highly porous nanocomposite as the sensing layer and added an extra insulating layer to the sensor, which gave it capabilities of both types of sensors.