A Yale-led team of physicists has discovered a circular pattern in the movement of electrons in a group of quantum materials known as “strange metals.”
Graphene is a two-dimensional wonder material that has been suggested for a wide range of applications in energy, technology, construction, and more since it was first isolated from graphite in 2004.
This single layer of carbon atoms is tough yet flexible, light but with high resistance, with graphene calculated to be 200 times more resistant than steel and five times lighter than aluminum.
Graphene may sound perfect, but it very literally is not. Isolated samples of this 2D allotrope aren’t perfectly flat, with its surface rippled. Graphene can also feature structural defects that can, in some cases, be deleterious to its function and, in other instances, can be essential to its chosen application. That means that the controlled implementation of defects could enable fine-tuning of the desired properties of two-dimensional crystals of graphene.
Cities can be obstacle courses for communications signals. A radio signal must travel from a cell phone to a router to a cell tower, and onward to its recipient—all while bouncing between walls, buildings and other structures. When it hits an obstacle, the radio wave gets scattered, diminishing the signal. This in turn reduces the bandwidth. At the same time, the signal must compete with the bandwidth needs of numerous other devices in the area. All this reduces the amount of information the signal can communicate.
Newly developed small, lightweight reflective surfaces could revolutionize communications in crowded environments by providing unprecedented control over electromagnetic signals, like radio waves.
Historically, engineers have used repeaters—electronic devices that receive a signal and retransmit it—to help these communications signals cover longer distances and get around obstacles, but this technology is reaching its limits. Now, engineers are looking to modify the behavior of the communications signal itself. Enter reconfigurable intelligent surfaces (RIS).
Materials that are both strong and lightweight could improve everything from cars to body armor. But usually, the two qualities are mutually exclusive. Now, University of Connecticut researchers and colleagues have developed an extraordinarily strong, lightweight material using two unlikely building blocks: DNA and glass.
“For the given density, our material is the strongest known,” says Seok-Woo Lee, a materials scientist at UConn. Lee and colleagues from UConn, Columbia University, and Brookhaven National Lab reported the details on July 19 in Cell Reports Physical Science.
Strength is relative. Iron, for example, can take seven tons of pressure per square centimeter. But it’s also very dense and heavy, weighing 7.8 grams/cubic centimeter. Other metals, such as titanium, are stronger and lighter than iron. And certain alloys combining multiple elements are even stronger. Strong, lightweight materials have allowed for lightweight body armor, better medical devices and made safer, faster cars and airplanes.
A team of researchers with Cambridge University created what they’re describing as synaptic devices — a material that can both work as a storage and memory medium while promising a significant jump in.
“My hope is that this finding will encourage materials researchers to consider that, under the right circumstances, materials can do things we never expected,” Demkowicz concluded.
The study is published in the journal Nature.
Self-healing metals are an exciting area of research in the field of materials science. The term refers to metals that have the ability to heal themselves after being damaged or degraded.
A research team led by Prof. Chen Xianhui from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS), collaborating with the team led by Prof. Sun Jian from Nanjing University, realized a new high superconducting transition temperature of 36 K in elemental materials under high pressure. Their study was published in Physical Review Letters.
Elemental materials provide clean and fundamental platforms for studying superconductivity. Since the discovery of superconductivity in the element mercury by Dutch scientist Heike Kamerlingh Onnes in 1911, more than 50 elements in total have been found to show superconductivity under atmospheric environments or high pressures. However, most elements have low superconducting critical temperatures (Tc), with the highest previous elemental Tc of 26 K being achieved by elemental titanium (Ti) at high pressures.
Previous studies revealed that elemental scandium (Sc) undergoes four structural phase transitions under pressure. Due to the limitations of early high-pressure experimental techniques, mysteries of the superconductivity of elemental Sc at higher pressures have yet to be untangled.
Microscopic cracks vanish in experiments, revealing possibility of self-healing machines.
In a groundbreaking discovery, scientists have for the first time observed metal spontaneously healing its microscopic cracks, upending traditional material theories. This observation could lead to self-healing machines, significantly enhancing their safety and lifespan. The phenomenon, confirming a theory proposed in 2013, may pave the way for an engineering revolution, though further research is necessary to fully understand its practical applicability.
Discovery of Self-healing Metal Phenomenon.
The ancient Romans were master builders and engineers, perhaps most famously represented by the still-functional aqueducts. And those architectural marvels rely on a unique construction material: pozzolanic concrete, a spectacularly durable material that gave Roman structures their incredible strength.
Even today, one of their structures – the Pantheon, still intact and nearly 2,000 years old – holds the record for the world’s largest dome of unreinforced concrete.
The properties of this concrete have generally been attributed to its ingredients: pozzolana, a mix of volcanic ash – named after the Italian city of Pozzuoli, where a significant deposit of it can be found – and lime. When mixed with water, the two materials can react to produce strong concrete.
A breakthrough study by the University of Washington.
Founded in 1,861, the University of Washington (UW, simply Washington, or informally U-Dub) is a public research university in Seattle, Washington, with additional campuses in Tacoma and Bothell. Classified as an R1 Doctoral Research University classification under the Carnegie Classification of Institutions of Higher Education, UW is a member of the Association of American Universities.
