A proposed lab-based quantum sensor could precisely measure within seconds the warping of spacetime caused by Earth’s rotation.
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Nanotube Material Has Perfect Memory
A carbon nanotube foam springs back to its initial state, regardless of the speed of the compression, a property that could lead to a new type of shock absorber.
Spongy materials can spring back following compression, but they don’t return exactly to their original shape. New experiments show that a foam made with carbon nanotubes snaps back to its initial shape, implying a perfect mechanical “memory” [1]. The material is also uniquely insensitive to deformation rate, behaving the same under fast and slow compressions. The researchers found that this combination of memory and rate-independence leads to an unusual property: The material’s response to mechanical shocks can be adjusted by appropriately compressing it before the shock. They imagine using this foam in “smart” helmets that reduce injury risk by controlling the propagation of impact energy.
Polymer foams—like the ones in some mattresses—can spring back, but viscosity effects cause irreversible changes to the internal structure, preventing the material from returning to its initial state. With repeated cycles of compression and release, the material drifts further from its original condition. “People refer to this as fading memory,” says Ramathasan Thevamaran from the University of Wisconsin–Madison. He and his colleagues have found a material that isn’t so forgetful.
Physicists extend the search for quantum black holes at the LHC
Physicists at UC Santa Barbara have extended the search for evidence of microscopic black holes produced at the Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN). The formation of these tiny, fleeting objects at the LHC represents one way theorists have sought to resolve anomalies in our understanding of the basic structure of spacetime, while the method used to look for them demonstrates a new way of searching for new particles.
“Had we found evidence, we could have begun to directly study quantum gravity,” said Tamas Vami, a researcher in the Compact Muon Solenoid (CMS) experiment who is conducting his postdoctoral work under the guidance of UCSB physics professor Joe Incandela. “It’s a step toward unifying all of the known fundamental forces, which has been a goal of physicists for more than a century.”
But a null result does not make for a fruitless search, said Incandela Lab graduate student researcher Danyi Zhang. Quite the opposite.
Stacked 2D materials reveal room-temperature multiferroicity and voltage-controlled magnetism
Multiferroics are materials that simultaneously exhibit two or more ferroic orders—stable arrangements of physical properties that can be switched using an external stimulus. These materials could be highly advantageous for the development of various technologies, including non-volatile, low-power memory devices, spintronic devices, miniaturized electronics, neuromorphic hardware, sensors and magnetoelectric devices.
The key advantage of multiferroics is that their different ferroic orders can be coupled, for instance allowing engineers to alter magnetic behavior using an electric voltage. Despite their promise, synthesizing multiferroics that are stable, ultrathin and controllable at room temperature has so far proved challenging.
Researchers at the University of Maryland and other institutes recently demonstrated an approach for creating van der Waals heterostructures that exhibit multiferroicity at room temperature.
Human brain has a split origin, new research suggests
For centuries, scientists have thought of the brain as a single, unified organ. But new research led by Stanford Medicine reveals that what we call the brain is two distinct organs that evolved independently over hundreds of millions of years.
The discovery overturns a prevailing model of brain development. For decades, researchers have subscribed to the theory that a single progenitor cell early in development gives rise to the entire brain. This model suggested all parts of the brain shared a common developmental origin.
The new findings show that the human brain consists of two ancient nervous systems packaged together—a more primitive part that regulates our hearts’ beating, breathing and other functions, and another that makes us distinctly human, capable of poetry, mathematics and wondering about our own origins.
Amino acids and a bone mineral may help control magnesium implant breakdown, three student papers suggest
Seeing a bachelor’s thesis published in a scientific journal is relatively uncommon. For three theses linked to the same research group to result in scientific publications within just three months is downright rare. Yet that is exactly what has happened in Elsebeth Schröder’s research group at the Division of Quantum Device Physics.
To celebrate the milestone, Schröder invited all three student teams to a cake party at the Department of Microtechnology and Nanoscience.
“It feels fantastic, of course. I certainly wasn’t expecting this,” says Alva Limbäck, whose article “A density functional theory study of amino acids on pristine Mg(0001) and with sparse alloying elements” was published in Applied Surface Science in August, together with fellow students Olof Hildeberg, John Bolin and Amanda Goold.
Laser experiments recreate solar flare physics and reveal consistent magnetic reconnection rates
Magnetic reconnection is a process that occurs when the magnetic fields of a conductive plasma quickly rearrange and release massive amounts of stored magnetic energy. It is widely thought to be the underlying mechanism behind cosmic events such as solar flares and substorms in Earth’s magnetosphere.
Now, researchers from Kyushu University have used high-power lasers to recreate and investigate this puzzling physical phenomenon of magnetic reconnection in a controlled environment. Their results indicate that fast magnetic reconnection is governed by the local physics of the reconnection layer rather than the properties of the surrounding plasma.
Briefly, magnetic reconnection involves the splicing and reconnection of magnetic field lines pointing in opposite directions as two plasma flows meet, causing plasma heating and high-speed plasma outflows.
Coffee on the nanoscale: Graphene oxide membrane removes half the caffeine while retaining key compounds
The humble coffee filter has the relatively simple job of letting the coffee through and leaving the grounds behind. But researchers from the ARC Center of Excellence for Carbon Science and Innovation (COE-CSI) are exploring whether a filter operating on the molecular scale can do something much more difficult: separate the caffeine from the coffee itself.
It’s no ordinary challenge. A cup of coffee isn’t simply water and caffeine; it’s a mixture of various chemical compounds, many of which contribute to its flavor, aroma and other characteristics. Removing caffeine while leaving the things that make coffee taste like coffee means distinguishing between molecules at an extraordinarily small scale.
For UNSW Team Graphene master’s research student Yihan Tian, the challenge had plenty of appeal. Not only is she a huge fan of coffee, but the science itself also excites her.
Pilot system couples seawater desalination with hydrogen production
Seawater holds enormous potential for green hydrogen production, but realizing that potential remains far from straightforward. Direct seawater electrolysis can damage electrodes, whereas conventional freshwater electrolysis loses much of its energy as low-grade waste heat. Researchers have now found a way to harness this otherwise wasted heat, using it to desalinate seawater and produce fresh water alongside hydrogen.
In a study published in Nature Energy on Sept. 15, a team led by Prof. Deng Dehui and Associate Prof. Liu Yanting from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) proposed a “seawater to hydrogen and fresh water (STHW)” route that couples alkaline water electrolysis (AWE) with low-temperature vacuum distillation desalination.
The STHW process uses waste heat generated during AWE to drive low-temperature seawater desalination, producing fresh water for electrolysis and external use. The resulting concentrated brine can also be used for resource recovery, including salt, uranium and bromine.