When an ordinary electrical conductor—such as a metal wire—is connected to a battery, the electrons in the conductor are accelerated by the electric field created by the battery. While moving, electrons frequently collide with impurity atoms or vacancies in the crystal lattice of the wire, and convert part of their motional energy into lattice vibrations. The energy lost in this process is converted into heat that can be felt, for example, by touching an incandescent light bulb.
MIT physicists and colleagues have created a five-lane superhighway for electrons that could allow ultra-efficient electronics and more. The work, reported in the May 9 issue of Science, is one of several important discoveries by the same team over the last year involving a material that is essentially a unique form of pencil lead.
😗Year 2022
Superconductivity is reported in magic-angle twisted four-layer and five-layer graphene systems. While they find that all magic-angle graphene systems fit into a unified hierarchy of systems that share a set of flat bands in their electronic band structures, they also report that there is a key distinction between magic-angle twisted bilayer graphene and the other family members, related to the difference in the way the electrons move between the layers in a magnetic field.
A ‘cage of cages’ is how scientists have described a new type of porous material, unique in its molecular structure, that could be used to trap carbon dioxide and another, more potent greenhouse gas.
Synthesized in the lab by researchers in the UK and China, the material is made in two steps, with reactions assembling triangular prism building blocks into larger, more symmetrical tetrahedral cages – producing the first molecular structure of its kind, the team claims.
The resulting material, with its abundance of polar molecules, attracts and holds greenhouse gasses such as carbon dioxide (CO2) with strong affinity. It also showed excellent stability in water, which would be critical for its use in capturing carbon in industrial settings, from wet or humid gas streams.
Borophene is already thinner and more conductive than graphene, and scientists have altered it to make it even more special.
Questions to inspire discussion.
What is the potential impact of humanoid robots on human labor?
—Humanoid robots are on the verge of disrupting human labor across various industries, leading to a new era of material superabundance and prosperity within the next 10 to 20 years.
The newfound black hole, an intense, light-trapping abyss which has been named Gaia BH3, lurks just 1,926 light-years from Earth in the Aquila constellation. (That makes it the second closest black hole to Earth after Gaia BH1, which resides at 1,500 light-years away and is three times lighter than Gaia BH3.) The so-called “sleeping giant” — so named because unlike its ilk, the dormant black hole doesn’t appear to be shredding its companion star to pieces — birthed out of the imminent collapse of a once-massive star. It is the first direct link between a black hole and a progenitor star that was deprived of metals heavier than hydrogen and helium, according to the new study published in April in the journal Astronomy and Astrophysics.
The discovery confirms a leading theory of stellar evolution that posits high-mass black holes are remnants of stars that are low on metals. Such metal-poor stars have damped mass-eroding winds compared to their metal-rich counterparts, and thus have more material available to form heavier black holes. Astronomers normally time announcements of science discoveries at the same time as data release, in this case no sooner than early 2026, but “you cannot hide this kind of discovery from the community for two years,” says Panuzzo. “It is a unique case of publication based on the preliminary data because the data is exceptional and also something that’s very interesting for the community.”