Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: materials – Page 284

Ferroelectric Semiconductors Could Mix Memory and Logic

FSJs (Ferroelectric Semiconductor Junction) in neuromorphic chips.

Engineers at Purdue University and at Georgia Tech have constructed the first devices from a new kind of two-dimensional material that combines memory-retaining properties and semiconductor properties. The engineers used a newly discovered ferroelectric semiconductor, alpha indium selenide, in two applications: as the basis of a type of transistor that stores memory as the amount of amplification it produces; and in a two-terminal device that could act as a component in future brain-inspired computers. The latter device was unveiled last month at the IEEE International Electron Devices Meeting in San Francisco.

Ferroelectric materials become polarized in an electric field and retain that polarization even after the field has been removed. Ferroelectric RAM cells in commercial memory chips use the former ability to store data in a capacitor-like structure. Recently, researchers have been trying to coax more tricks from these ferroelectric materials by bringing them into the transistor structure itself or by building other types of devices from them.

In particular, they’ve been embedding ferroelectric materials into a transistor’s gate dielectric, the thin layer that separates the electrode responsible for turning the transistor on and off from the channel through which current flows. Researchers have also been seeking a ferroelectric equivalent of the memristors, or resistive RAM, two-terminal devices that store data as resistance. Such devices, called ferroelectric tunnel junctions, are particularly attractive because they could be made into a very dense memory configuration called a cross-bar array. Many researchers working on neuromorphic- and low-power AI chips use memristors to act as the neural synapses in their networks. But so far, ferroelectric tunnel junction memories have been a problem.

Lucy Mission Overview: Journey to Explore the Trojan Asteroids

Launching in late 2021, Lucy will be the first space mission to explore the Trojan asteroids. These are a population of small bodies that are left over from the formation of the solar system. They lead or follow Jupiter in their orbit around the Sun, and they may tell us about the origins of organic materials on Earth.

Lucy will fly by and carry out remote sensing on six different Trojan asteroids and will study surface geology, surface color and composition, asteroid interiors/bulk properties, and will look at the satellites and rings of the Trojans.

Influential electrons? Physicists uncover a quantum relationship

A team of physicists has mapped how electron energies vary from region to region in a particular quantum state with unprecedented clarity. This understanding reveals an underlying mechanism by which electrons influence one another, termed quantum “hybridization,” that had been invisible in previous experiments.

The findings, the work of scientists at New York University, the Lawrence Berkeley National Laboratory, Rutgers University, and MIT, are reported in the journal Nature Physics.

“This sort of relationship is essential to understanding a quantum electron system—and the foundation of all movement—but had often been studied from a theoretical standpoint and not thought of as observable through experiments,” explains Andrew Wray, an assistant professor in NYU’s Department of Physics and one of the paper’s co-authors. “Remarkably, this work reveals a diversity of energetic environments inside the same material, allowing for comparisons that let us spot how electrons shift between states.”

‘Superdiamond’ carbon-boron cages can trap and tap into different properties

A long-sought-after class of “superdiamond” carbon-based materials with tunable mechanical and electronic properties was predicted and synthesized by Carnegie’s Li Zhu and Timothy Strobel. Their work is published by Science Advances.

Carbon is the fourth-most– in the universe and is fundamental to life as we know it. It is unrivaled in its ability to form stable structures, both alone and with other elements.

A material’s properties are determined by how its are bonded and the structural arrangements that these bonds create. For -based materials, the type of bonding makes the difference between the hardness of diamond, which has three-dimensional “sp3” bonds, and the softness of graphite, which has two-dimensional “sp2” bonds, for example.

Company Is Using Plastic Bottles To Make Roads That Last 10x Longer Than Asphalt

Once the plastic road is done, it will look just like any other asphalt road. But the advantage is, this new road is more flexible. It can better sustain heat and cold. It will also stand stronger against elemental damages. And since this is an enhanced asphalt form, it will last ten times longer and is proven to be 60% stronger.

This is definitely good news for drivers and commuters. Roads stay longer which means there will be fewer cracks and potholes!

International Space Station astronauts play with fire for research

Playing with fire can be dangerous and never more so than when confined in a space capsule floating 250 miles above the Earth. But in the past week astronauts onboard the International Space Station have intentionally lit a series of blazes in research designed to study the behaviour of flames in zero gravity.

The scientists behind the experiment, called Confined Combustion, say it will help improve fire safety on the ISS and on future lunar missions by helping predict how a blaze might progress in low gravity conditions.

Dr Paul Ferkul, of the Universities Space Research Association, who is working on the project, said: “That is the immediate and most practical goal since NASA can use the knowledge to improve material selection and fire safety strategies.”

/* */