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A group of researchers led by Sir Andre Geim and Dr. Alexey Berdyugin at The University of Manchester have discovered and characterized a new family of quasiparticles named ‘Brown-Zak fermions’ in graphene-based superlattices.

The team achieved this breakthrough by aligning the atomic lattice of a graphene layer to that of an insulating boron nitride sheet, dramatically changing the properties of the graphene sheet.

The study follows years of successive advances in graphene-boron nitride superlattices which allowed the observation of a fractal pattern known as the Hofstadter’s butterfly—and today (Friday, November 13) the researchers report another highly surprising behavior of particles in such structures under applied magnetic field.

In recent years, researchers have been trying to develop new types of highly performing electronic devices. As silicon-based devices are approaching their maximum performance, they have recently started exploring the potential of fabricating electronics using alternative superconductors.

Two-dimensional (2-D) semiconductors, such as graphene or tungsten diselenide (WSe₂), are particularly promising for the development of electronics. Unfortunately, however, controlling the electronic properties of these materials can be very challenging, due to the limited amount of space within their lattices to incorporate impurity dopants (a process that is critical for controlling the carrier type and electronic properties of semiconductor materials).

Researchers at University of California, Los Angeles, have recently devised an approach that could enable the development of programmable devices made of 2-D semiconductors. This approach, presented in a paper published in Nature Electronics, leverages a superionic phase transition in silver iodide to tailor the carrier type within devices made of WSe₂ via a process called switchable ionic doping.

Researchers discover an unexpected new class of superconducting material.

Superconducting materials are traditionally classed into two types: s-wave and d-wave. A third type, p-wave, has long been predicted. Now, however, researchers in the US, Germany and Japan say they may have discovered a fourth, unexpected type of superconductor: g-wave. The result, obtained thanks to high-precision resonant ultrasound spectroscopy measurements on strontium ruthenate, could shed fresh light on the Cooper pairing mechanisms in so-called unconventional superconductors.

Engineers at Cornell University have developed a new technique for 3D printing metallic objects – and it involves blasting titanium particles at supersonic speeds. The resulting metals are very porous, which makes them particularly useful for biomedical objects like implants and replacement joints.

Traditional 3D printing involves a nozzle depositing plastic, hydrogels, living cells or other materials layer by layer to build up an object. Metal parts and objects are usually 3D printed in other ways, such as firing a laser at a bed of metal powder to selectively melt sections into the desired shape, or firing metal powder at high speeds at a substrate to fuse the particles together.

The latter method is known as “cold spray,” and the new technique expands on that base. The Cornell team blasted titanium alloy particles, each measuring between 45 and 106 microns wide, at speeds up to 600 m (1,969 ft) per second (for reference, the speed of sound in air is around 340 m (1,115 ft) per second). The team calculated this as the ideal speed – any faster, and the particles would disintegrate too much on impact to bond to each other.

Groundbreaking science is often the result of true collaboration, with researchers in a variety of fields, viewpoints and experiences coming together in a unique way. One such effort by Clemson University researchers has led to a discovery that could change the way the science of thermoelectrics moves forward.

Graduate research assistant Prakash Parajuli; research assistant professor Sriparna Bhattacharya; and Clemson Nanomaterials Institute (CNI) Founding Director Apparao Rao (all members of CNI in the College of Science’s Department of Physics and Astronomy) worked with an international team of scientists to examine a highly efficient thermoelectric material in a new way—by using light.

Their research has been published in the journal Advanced Science and is titled “High zT and its origin in Sb-doped GeTe single crystals.”

“Anything you take from Earth to the moon is an added weight that you don’t want to carry, so if you can make these materials in situ it saves you a lot of time, effort and money,” said Ian Mellor, the managing director of Metalysis, which is based in Sheffield.

Analyses of rocks brought back from the moon reveal that oxygen makes up about 45% of the material by weight. The remainder is largely iron, aluminium and silicon. In work published this year, scientists at Metalysis and the University of Glasgow found they could extract 96% of the oxygen from simulated lunar soil, leaving useful metal alloy powders behind.

NASA and other space agencies are in advanced preparations to return to the moon, this time to establish a permanent lunar base, or “moon village” where nations will operate alongside private companies on critical technologies such as life support, habitat construction, energy generation and food and materials production.

Skeleton Technologies and the Karlsruhe Institute of Technology (KIT) say they have developed a graphene-based battery with a 15-second charging time, as well as charging cycles counted in the hundreds of thousands.

The so-called SuperBattery’s key component is Skeleton’s patented Curved Graphene carbon material, which enables the high power and long lifetime of ultracapacitors to be applied in a graphene battery.

“The SuperBattery is a game-changer for the automotive industry. Together with Li-ion batteries, they have it all: high energy and power density, long lifetime and 15-second charging time,” said Skeleton Technologies CEO Taavi Madiberk.

David Fischer, an MIT Energy Fellow at the Plasma Science and Fusion Center, is observing ways irradiation damages thin high-temperature superconductor tapes in the design of ARC, a fusion pilot plant concept.

Superconductivity is a phenomenon where an electric circuit loses its resistance and becomes extremely efficient under certain conditions. There are different ways in which this can happen which were thought to be incompatible. For the first time, researchers discover a bridge between two of these methods to achieve superconductivity. This new knowledge could lead to a more general understanding of the phenomena, and one day to applications.

If you’re like most people, there are three states of matter in your everyday life: solid, liquid, and gas. You might be familiar with a fourth state of matter called plasma, which is like a gas that got so hot all its constituent atoms came apart, leaving behind a super hot mess of subatomic particles. But did you know about a so-called fifth state of matter at the complete opposite end of the thermometer? It’s known as a Bose-Einstein condensate (BEC).

“A BEC is a unique state of matter as it is not made from particles, but rather waves,” said Associate Professor Kozo Okazaki from the Institute for Solid State Physics at the University of Tokyo. “As they cool down to near absolute zero, the atoms of certain materials become smeared out over space. This smearing increases until the atoms — now more like waves than particles — overlap, becoming indistinguishable from one another. The resulting matter behaves like it’s one single entity with new properties the preceding solid, liquid or gas states lacked, such as superconduction. Until recently superconducting BECs were purely theoretical, but we have now demonstrated this in the lab with a novel material based on iron and selenium (a nonmetallic element).”