Twisted bi-layer graphene displays unique quantum behavior

Scientists studying two different configurations of bilayer graphene have detected electronic and optical interlayer resonances. In these resonant states, electrons bounce back and forth between the two atomic planes in the 2-D interface at the same frequency. By characterizing these states, they found that twisting one of the graphene layers by 30 degrees relative to the other, instead of stacking the layers directly on top of each other, shifts the resonance to a lower energy. From this result they deduced that the distance between the two layers increased significantly in the twisted configuration, compared to the stacked one. When this distance changes, so do the interlayer interactions, influencing how electrons move in the bilayer system. An understanding of this electron motion could inform the design of future quantum technologies for more powerful computing and more secure communication.

“Today’s computer chips are based on our knowledge of how electrons move in semiconductors, specifically silicon,” said first and co-corresponding author Zhongwei Dai, a postdoc in the Interface Science and Catalysis Group at the Center for Functional Nanomaterials (CFN) at the U.S. Department of Energy (DOE)’s Brookhaven National Laboratory. “But the physical properties of silicon are reaching a physical limit in terms of how small transistors can be made and how many can fit on a chip. If we can understand how electrons move at the small scale of a few nanometers in the reduced dimensions of 2-D materials, we may be able to unlock another way to utilize electrons for quantum information science.”

New model describes geometric features of carbon networks and their influence on the material's properties

Scientists at Tohoku University and colleagues in Japan have developed a mathematical model that abstracts the key effects of changes to the geometries of carbon material and predicts its unique properties.

Geometric model of 3D curved graphene with chemical dopants image

Scientists generally use mathematical models to predict the properties that might emerge when a material is changed in certain ways. Changing the geometry of three-dimensional (3D) graphene, which is made of networks of carbon atoms, by adding chemicals or introducing topological defects, can improve its catalytic properties, for example. But it has been difficult for scientists to understand why this happens exactly.

Researchers develop a new method for quick and efficient synthesis of nanographenes

A research team at Nagoya University in Japan has developed a new technique for synthesizing nanographenes, remarkable materials with a vast number of potential structures that can even exhibit electric and magnetic characteristics beyond those of graphene.

Since each nanographene exhibits different physical characteristics, the key to applied nanographene study is to determine the relationship between the structure and characteristics of as many nanographenes as possible.

Gnanomat announced new commercially available Graphene-Silver nanocomposite

Gnanomat recently announced the launch of its new commercially-available graphene-based nanocomposite.

A new Graphene-Silver nanocomposite commercially available by Gnanomat image

Graphene – Silver nanocomposite, a product supplied as a dry powder, is made of pristine graphene coated with silver nanoparticles. This type of material has been shown to have great potential in scientific literature, in applications such as inks on textiles for highly conductive wearable electronics, electrochemical sensors, catalyst, antibacterial activity and detection of heavy metal ions.

Researchers examine 'Kagome' graphene and report promising results

Researchers from the Department of Physics and the Swiss Nanoscience Institute at the University of Basel, working in collaboration with the University of Bern, have recently produced and studied a compound referred to as "kagome graphene", that consists of a regular pattern of hexagons and equilateral triangles that surround one another. The name kagome comes from the old Japanese art of kagome weaving, in which baskets are woven in the same pattern.

Kagome graphene revealed to have fascinating properties imageKagome graphene is characterized by a regular lattice of hexagons and triangles. Credit: R. Pawlak, Department of Physics, University of Basel

The team's measurements have reportedly delivered promising results that point to unusual electrical or magnetic properties of the material.