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

Researchers at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory and the University of California, Berkeley, have developed a method to stabilize the edges of graphene nanoribbons and directly measure their unique magnetic properties. The researchers found that by substituting some of the carbon atoms along the ribbon's zigzag edges with nitrogen atoms, they could discretely tune the local electronic structure without disrupting the magnetic properties. 

Researchers at The Ohio State University have shown that atomic-scale magnetic patterns looking like a hedgehog's spikes could enable the future development of hard disks with massively larger capacities than today's devices. The researchers used a scanning tunneling microscope, which provided pictures of the magnetic patterns with atomic resolution. The images revealed that the "body" of the hedgehog was only 10 nanometers wide, which is smaller than today's magnetic bits (about 50 nanometers). This finding could help data centers keep up with the exponentially increasing demand for video and cloud data storage.

Researchers at the University of Pennsylvania, Pennsylvania State University, the University of California at Los Angeles, the University of Dayton, the U.S. Department of Energy’s Brookhaven National Laboratory, the Air Force Research Laboratory, and AIXTRON Ltd in Cambridge, United Kingdom, have developed a new method of manufacturing atomically thin (five-atoms thick) superlattices – semiconductor films that detect and emit light. One-atom-thick materials generally take the form of a lattice, or a layer of geometrically aligned atoms that form a pattern specific to each material. A superlattice is made up of lattices of different materials stacked upon one another and has completely new optical, chemical, and physical properties.

Researchers at Wake Forest School of Medicine have discovered that a nanoparticle therapeutic enhances cancer immunotherapy and is a possible new approach in treating malignant pleural effusion (MPE). MPE is the accumulation of fluid between the chest wall and lungs and is accompanied by malignant cells and/or tumors. Clinical evidence suggests that MPE comprises abundant tumor-associated immune cells that prevent the body’s immune system from recognizing and eliminating the cancer. To mitigate this issue, the researchers developed a nanoparticle called liposomal cyclic dinucleotide for targeted activation of an immune pathway that reprograms tumor-associated immune cells to active anti-tumor ones. 

A team of researchers from Harvard University and MIT has observed exotic fractional states at low magnetic field in twisted bilayer graphene for the first time. The researchers were interested in a specific exotic quantum state, known as fractional Chern insulators. Chern insulators conduct electricity on their surface or edge but not in the middle. To build their insulator, the researchers used two sheets of graphene twisted together at the so-called magic angle. 

Researchers at North Carolina State University have demonstrated a new design for thermal actuators that can be used to create rapid movement in soft robotic devices. The researchers layered two materials on top of each other, with silver nanowires in the middle. The two materials have different coefficients of thermal expansion, so they expand at different rates as they heat up. This layered material was then shaped into a design that gives it a default curvature in one direction. When voltage is applied to the silver nanowires, the material heats up, making it bend in the other direction. 

In mouse models of different types of cancer, scientists at The Ohio State University boosted activation of T cells inside tumors in a way that improved their interactions with an antibody therapy currently being tested in clinical trials. The researchers injected nanoparticles carrying messenger RNA, molecules that translate genetic information into proteins, directly into the tumor site to help T cells generate specific receptors on their surfaces. Experimental monoclonal antibodies delivered six hours later could then bind to those receptors to carry out their cancer cell-killing functions.

Spin waves, a change in electron spin that propagates through a material, could fundamentally alter how devices store and carry information. But the properties that make them so powerful also make them nearly impossible to measure. In a previous study, researchers demonstrated the ability to both excite and detect spin waves in a two-dimensional graphene magnet, but they couldn't measure any of the wave's properties. Now, researchers at Harvard University have demonstrated a new way to measure the properties of spin waves in graphene.

Researchers at the National Institute of Standards and Technology and Columbia Engineering have discovered a new method to improve the toughness of materials, which could lead to stronger versions of body armor and bulletproof glass. The researchers created films composed of tiny glass spheres, called silica nanoparticles, each covered with chains of a polymer known as polymethacrylate, and made them targets in miniature impact tests that showed off the material's enhanced toughness. 

A group of Carnegie Mellon University mechanical engineering researchers has developed a sensor system that was able to successfully detect levels of the neurotransmitter dopamine down to femtomolar concentrations. The team used a technique, known as aerosol jet 3D nanoparticle printing, that allowed them to build tiny micropillars using silver nanoparticles to create an incredibly sensitive detection system. This detection system consists of a three-dimensional electrode placed into a microfluidic channel, where samples are pumped through.