(Funded by the National Science Foundation)
Physicists at the Massachusetts Institute of Technology (MIT) have taken a key step toward solving the puzzle of what leads electrons to split into fractions of themselves. The new work is an effort to make sense of a discovery that was reported earlier this year by other physicists at MIT, who found that electrons appear to exhibit “fractional charge” in pentalayer graphene – a configuration of five graphene layers that are stacked atop a similarly structured sheet of boron nitride. Through calculations of quantum mechanical interactions, the scientists showed that the electrons form a sort of crystal structure, the properties of which are ideal for fractions of electrons to emerge. “This crystal has a whole set of unusual properties that are different from ordinary crystals, and leads to many fascinating questions for future research,” said Senthil Todadri, the scientist who led the new study.

(Funded by the National Institutes of Health and the National Science Foundation)
Researchers at the University of Massachusetts Amherst and the University of Massachusetts-Chan Medical School in Springfield, MA, have invented a new, sprayable delivery system for psoriasis medication that can be applied easily and locally to psoriasis lesions. The delivery system makes use of nanoparticles that contain psoriasis drugs, and these nanoparticles act like a trojan horse – the immune cells do not recognize the nanoparticles as a threat, but the medication they carry disrupts the overactive immune response. The researchers designed and tested nanoparticles in different shapes: rods, ellipses and spheres and discovered that nanorods inhibited 3.8 times more inflammation due to psoriasis than nanoellipses and 4.5 times more than nanospheres.

(Funded by the National Science Foundation and the U.S. Department of Energy)
Researchers from Florida State University, the Shanghai Institute of Microsystem and Information Technology, and Wuhan University have revealed how various physical manipulations of graphene, such as layering and twisting, impact its optical properties and conductivity. The researchers found that the optical conductivity of twisted bilayer graphene is not heavily impacted by such manipulations and instead depends more on how the material’s geometry structure changes by interlayer twisting. To conduct the study, the team captured images of plasmons – tiny waves of energy that happen when electrons in a material move together – that appeared in various regions of the twisted bilayer graphene.

(Funded by the National Science Foundation)
Cornell University researchers have made headway into understanding how twisted bilayer graphene becomes a superconductor. In 2023, the scientists developed a theoretical formalism to compute the highest possible superconducting transition temperature in any material obtained by stacking and twisting two-dimensional materials. For the current work, the scientists applied this theoretical formalism to twisted bilayer graphene. “One of the remarkable properties of twisted bilayer graphene is the associated tunability,” said Debanjan Chowdhury, one of the scientists involved in this study. “You have unprecedented control over temperature and the twist angle – the tiny electric fields that are applied to switch the material from being an insulator versus a superconductor – making it very easy to explore all sorts of exciting regimes in this material.”

(Funded by the National Science Foundation)
Researchers at William & Mary have measured the strength and stretchability of minuscule nanofibrils present in the silk spun by the southern house spider. The core of a spider silk strand is composed of two distinct warps that form helical loops around a central foundation fiber. The tiniest fibers, nanofibrils, are spun into a mesh that surrounds those supporting structures. The researchers found that the nanofibrils in the southern house spider’s silk could stretch 11 times their original length, more than twice the amount of any spider silk previously tested. “As amazing as spider silk as a whole is, looking at these tiny fibrils, they are even stretchier,” said Hannes Schniepp, one of the scientists involved in this study.