Researchers at the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have designed a graphene device that switches from a superconducting material to an insulator and back again to a superconductor — all with a flip of a switch. The team shared that the device exhibits this unique versatility while being thinner than a human hair.

Views of the trilayer graphene/boron nitride heterostructure device as seen through an optical microscope. The gold, nanofabricated electric contacts are shown in yellow; the silicon dioxide/silicon substrate is shown in brown and the boron nitride flakes

"Usually, when someone wants to study how electrons interact with each other in a superconducting quantum phase versus an insulating phase, they would need to look at different materials. With our system, you can study both the superconductivity phase and the insulating phase in one place," said Guorui Chen, the study's lead author and a postdoctoral researcher in the lab of Feng Wang, who led the study. Wang, a faculty scientist in Berkeley Lab's Materials Sciences Division, is also a UC Berkeley physics professor.

A team of researchers led by Columbia University have developed a new method to finely tune adjacent layers of graphene, in a research that provides new insights into the physics underlying the material's intriguing characteristics.

"Our work demonstrates new ways to induce superconductivity in twisted bilayer graphene, in particular, achieved by applying pressure," said Cory Dean, assistant professor of physics at Columbia and the study's principal investigator. "It also provides critical first confirmation of last year's MIT results - that bilayer graphene can exhibit electronic properties when twisted at an angle - and furthers our understanding of the system, which is extremely important for this new field of research".

A study by Brazilian physicist Aline Ramires with Jose Lado, a Spanish-born researcher at the Swiss Federal Institute of Technology (ETH Zurich), showed that a simple sheet of graphene has fascinating properties due to a quantum phenomenon in its electron structure called Dirac cones. The system becomes even more interesting if it comprises two superimposed graphene sheets, and one is very slightly turned in its own plane so that the holes in the two carbon lattices no longer completely coincide. For specific angles of twist, the bilayer graphene system displays exotic properties such as superconductivity.

The researchers found that the application of an electrical field to such a system produces an effect identical to that of an extremely intense magnetic field applied to two aligned graphene sheets. "I performed the analysis, and it was computationally verified by Lado," Ramires said. "It enables graphene's electronic properties to be controlled by means of electrical fields, generating artificial but effective magnetic fields with far greater magnitudes than those of the real magnetic fields that can be applied."

Researchers at MIT and Harvard University have found that graphene can be tuned to behave at two electrical extremes: as an insulator, in which electrons are completely blocked from flowing; and as a superconductor, in which electrical current can stream through without resistance.

Researchers in the past, including this team, have been able to synthesize graphene superconductors by placing the material in contact with other superconducting metals — an arrangement that allows graphene to inherit some superconducting behaviors. In this new work, the team found a way to make graphene superconduct on its own, demonstrating that superconductivity can be an intrinsic quality in the purely carbon-based material.

Researchers at the University of Cambridge, managed to activate graphene's potential to superconduct by coupling it with a material called praseodymium cerium copper oxide (PCCO). The researchers suggest that superconductive graphene could have interesting applications; It could be used to create new types of superconducting quantum devices for high-speed computing, and it might also be used to prove the existence of a form of superconductivity known as "p-wave" superconductivity, which academics have been struggling to verify for many years.

Graphene's ability to superconduct has been speculated but thus far has only been achieved by doping it with, or by placing it on, a superconducting material - a process that can compromise some of its other properties. "Placing graphene on a metal can dramatically alter the properties so it is technically no longer behaving as we would expect," the team stated. "What you see is not graphene's intrinsic superconductivity, but simply that of the underlying superconductor being passed on."

Saint Jean Carbon, a carbon science company engaged in the design and development of carbon materials and their applications, recently received (along with Western University) a grant from the The Natural Sciences and Engineering Research Council of Canada (NSERC) towards the development of graphene-based systems with special magnetic properties.

The $100,000 grant will be used to cover the cost of the lab work, testing, material creation and all research associated costs. The company stated that it aims to use the funds to get beyond the lab and into working prototypes, scaled models and future commercial production. In addition, SJC hopes that "the results will play a big role in the medical field as well in energy storage for electric cars and green energy creation".

The Fraunhofer Institute FEP and other partners at EU GLADIATOR project developed a functional flexible OLED lighting device based on graphene electrodes. This device is 2 x 1 cm in size - much larger the previous prototype developed as part of that project last year.

The graphene electrodes were produced in a CVD-based process. The graphene was deposited on a copper film, covered with a flexible polymer carrier and then the copper was etched away.

Saint Jean Carbon, a carbon science company engaged in the exploration of natural graphite properties and related carbon products, has announced the development of hybrid graphene sheets with superconductivity. The work is the ongoing development of a number of different areas of research between Saint Jean and University of Western Ontario.

The hybrid graphene nanosheets were created by depositing yttrium barium copper oxide (YBCO) superconductor particles and were developed by using the matrix-assisted pulsed laser evaporation (MAPLE) method. With increasing irradiation time, the amount of YBCO nanoparticles deposited on graphene is increased. In addition, the microstructures and elemental composition of YBCO nanoparticle deposited on graphene sheet by the MAPLE process were studied in terms of particle size and shape as a function of the deposition time/irradiation time. It is noted that the shape and size of the YBCO nanoparticles are more uniform with increasing the deposition time. When it increases to 2 hours, the average diameter of the spherical YBCO nanoparticles deposited on graphene sheets is around 50 ± 10 nm. This study demonstrates that MAPLE is a suitable process for depositing inorganic superconductor nanoparticles on graphene sheets without additional chemical agents.

Researchers at the University of Sussex in England have found that a hybrid material consisting of silver nanowires that are linked together with graphene could be a strong contender in the battle to replace indium tin oxide as the transparent conductor in touch screen displays.

This material is said to be much cheaper to use since only a small amount of it is necessary in order to attain the properties of ITO. The graphene, according to the team, acts as a linker between the nanowires, which means that the network does not need to be dense. The graphene is deposited onto a sprayed network of nanowires by film deposition.

Researchers from Korea's ETRI Institute developed the world's first transparent OLED prototype that uses a graphene transparent electrode. ETRI demonstrated the new display at the SID 2016 tradeshow.

The prototype display was 26x26 mm in size, with a resolution of 155x60 (121 PPI). The display was a monochrome (orange) display. In the display on show, the graphene-based electrodes were deposited on the backplane of the display.