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Jul 26, 2023

Map shows how you would be affected by a nuclear bomb

Posted by in categories: existential risks, military

A rather macabre interactive map demonstrates how the area you live in would be impacted if a nuclear bomb were to hit it. Nuclear war is as big a talking point these days as it ever has been. Advert With Russia and Ukraine still at war, Russian President Vladimir Putin has made some not-so-veiled threats about nuclear weapon use.

Jul 26, 2023

Researchers control the anomalous Hall effect and Berry curvature to create flexible quantum magnets

Posted by in categories: biotech/medical, computing, quantum physics

Some of our most important everyday items, such as computers, medical equipment, stereos, generators, and more, work because of magnets. We know what happens when computers become more powerful, but what might be possible if magnets became more versatile? What if one could change a physical property that defined their usability? What innovation might that catalyze?

It’s a question that MIT Plasma Science and Fusion Center (PSFC) research scientists Hang Chi, Yunbo Ou, Jagadeesh Moodera, and their co-authors explore in a new, open-access Nature Communications paper, “Strain-tunable Berry curvature in quasi-two-dimensional chromium telluride.”

Understanding the magnitude of the authors’ discovery requires a brief trip back in time: In 1,879, a 23-year-old graduate student named Edwin Hall discovered that when he put a magnet at right angles to a strip of metal that had a current running through it, one side of the strip would have a greater charge than the other. The was deflecting the current’s electrons toward the edge of the metal, a phenomenon that would be named the Hall effect in his honor.

Jul 26, 2023

Goddard, Wallops Engineers Test Printed Electronics in Space

Posted by in categories: futurism, space

Engineers successfully tested hybrid printed circuits at the edge of space in an April 25 sounding rocket flight from NASA’s Wallops Flight Facility near Chincoteague, Virginia. Electronic temperature and humidity sensors printed onto the payload bay door and onto two attached panels monitored the entire SubTEC-9 sounding rocket mission, recording data that was beamed to the ground. The experiment by aerospace engineer Beth Paquette and electronics engineer Margaret Samuels of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, sought to prove the space-readiness of printed electronics technology.


Printing electronic circuits on the walls and structures of spacecraft could help future missions do more in smaller packages.

Jul 26, 2023

Strong as Glass

Posted by in categories: biotech/medical, materials

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 report the details on July 19 in Cell Reports Physical Science.

Strength is relative. Iron, for example, can take 7 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. The easiest way to extend the range of an electric vehicle, for example, is not to enlarge the battery but rather make the vehicle itself lighter without sacrificing safety and lifetime. But traditional metallurgical techniques have reached a limit in recent years, and materials scientists have had to get even more creative to develop new lightweight high strength materials.

Jul 26, 2023

DARPA will soon make strong and reusable scrap wood

Posted by in categories: materials, sustainability

It turns out there’s a lot of scrap wood produced by the US Army. According to the US Army Corps of Engineers, more than 80 percent of solid waste produced at the Department of Defense (DoD) forward operating bases consists of scrap wood, cardboard, and paper. This equates to almost 13 pounds of waste per soldier per day that could be reused if handled properly, reducing garbage and supplying useful materials for construction.

DARPA’s new Waste Upcycling for Defense (WUD) program aims to produce a process for turning scrap wood, cardboard, and paper into lightweight, strong, and sustainable materials for reuse in a variety of DoD environments.

Jul 26, 2023

Building a quantum computer in reverse

Posted by in categories: computing, quantum physics

Scaling has long been recognized as a major hurdle for quantum processors, along with a need for advances in quantum error correction and the control of quantum gates.

However, while rapid progress has been made in the latter two, far less progress has been made in the development of a CMOS-based scalable system, where the devices and qubits are sufficiently identical that the number of external control signals increases slowly with the number of qubits.

Therefore the development, and taping-out, of a CMOS-based scaling architecture has taken on new significance, as scaling has become the most critical remaining task for building a commercially viable quantum computer.

Jul 26, 2023

Sampling frequency thresholds for the quantum advantage of the quantum approximate optimization algorithm

Posted by in categories: information science, quantum physics

We compare the performance of the Quantum Approximate Optimization Algorithm (QAOA) with state-of-the-art classical solvers Gurobi and MQLib to solve the MaxCut problem on 3-regular graphs. We identify the minimum noiseless sampling frequency and depth p required for a quantum device to outperform classical algorithms. There is potential for quantum advantage on hundreds of qubits and moderate depth with a sampling frequency of 10 kHz. We observe, however, that classical heuristic solvers are capable of producing high-quality approximate solutions in linear time complexity. In order to match this quality for large graph sizes N, a quantum device must support depth p > 11. Additionally, multi-shot QAOA is not efficient on large graphs, indicating that QAOA p ≤ 11 does not scale with N. These results limit achieving quantum advantage for QAOA MaxCut on 3-regular graphs.

Jul 26, 2023

Simulating Spacetime with Quantum Mechanical Materials

Posted by in categories: materials, quantum physics

At the annual APS Division of Atomic, Molecular and Optical Physics meeting, physicists made the case for a new way of modeling a universe.

Jul 26, 2023

Molecular highway for electrons in organic light-emitting diodes

Posted by in categories: computing, mobile phones, transportation

Organic light-emitting diodes (OLEDs) are now widely used. For use in displays, blue OLEDs are additionally required to supplement the primary colors red and green. Especially in blue OLEDs, impurities give rise to strong electrical losses, which could be partly circumvented by using highly complex and expensive device layouts. A team from the Max Planck Institute for Polymer Research has now developed a new material concept that potentially allows efficient blue OLEDs with a strongly simplified structure.

From televisions to smartphones: (OLEDs) are nowadays finding their way into many devices that we use every day. To display an image, they are needed in the three primary colors red, green and blue. In particular, for are still difficult to manufacture because blue light—physically spoken—has a , which makes the development of materials difficult.

Especially the presence of minute quantities of impurities in the material that cannot be removed plays a decisive role in the performance of these materials. These impurities— , for example—form obstacles for electrons to move inside the diode and participate in the light-generation process. When an electron is captured by such an obstacle, its energy is not converted into light but into heat. This problem, known as “charge trapping”, occurs primarily in blue OLEDs and significantly reduces their efficiency.

Jul 26, 2023

Three simple steps to make the longest graphene nanoribbon ever

Posted by in categories: particle physics, quantum physics

With 147 fused benzene rings and 920 conjugated atoms, the nanoribbon shows optoelectronic properties that could compete with quantum dots.