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Sep 23, 2019

Low-loss YIG-based magnonic crystals with large tunable bandgaps

Posted by in category: computing

O.o.


Control of spin waves in magnonic crystals is essential for magnon-based computing. Crystals made of ferromagnetic metals offer versatility in band structure design, but strong magnetic damping restricts their transmission efficiency. Yttrium iron garnet (YIG) with ultralow damping is the palpable alternative, yet its small saturation magnetization limits dipolar coupling between discrete units. Here, we experimentally demonstrate low-loss spin-wave manipulation in magnonic crystals of physically separated nanometer-thick YIG stripes. We enhance the transmission of spin waves in allowed minibands by filling the gaps between YIG stripes with CoFeB. Thus-formed magnonic crystals exhibit tunable bandgaps of 50–200 MHz with nearly complete suppression of the spin-wave signal. We also show that Bragg scattering on only two units produces clear frequency gaps in spin-wave transmission spectra. The integration of strong ferromagnets in nanometer-thick YIG-based magnonic crystals provides effective spin-wave manipulation and low-loss propagation, a vital parameter combination for magnonic technologies.

Sep 23, 2019

DNA is held together by hydrophobic forces

Posted by in category: biotech/medical

Researchers at Chalmers University of Technology, Sweden, have disproved the prevailing theory of how DNA binds itself. It is not, as is generally believed, hydrogen bonds which bind together the two sides of the DNA structure. Instead, water is the key. The discovery opens doors for new understanding in research in medicine and life sciences. The findings are published in PNAS.

DNA is constructed of two strands consisting of sugar molecules and phosphate groups. Between these two strands are nitrogen bases, the compounds that make up genes, with hydrogen bonds between them. Until now, it was commonly thought that those hydrogen bonds held the two strands together.

But now, researchers from Chalmers University of Technology show that the secret to DNA’s helical structure may be that the molecules have a hydrophobic interior, in an environment consisting mainly of water. The environment is therefore hydrophilic, while the DNA molecules’ nitrogen bases are hydrophobic, pushing away the surrounding water. When hydrophobic units are in a hydrophilic environment, they group together to minimize their exposure to the water.

Sep 23, 2019

Innovative orange juicer 3D prints bioplastic cups out of leftover orange peels

Posted by in categories: 3D printing, innovation

Designer Carlo Ratti Associati has unveiled the “Feel the Peel”, a combo orange juicer/3D printer that makes bioplastic cups out of leftover orange peels.

Sep 23, 2019

What will future jobs look like? Andrew McAfee

Posted by in categories: employment, robotics/AI

Economist Andrew McAfee suggests that, yes, probably, droids will take our jobs — or at least the kinds of jobs we know now.

Sep 23, 2019

Physicists invent a new way to search for dark matter using lasers

Posted by in categories: cosmology, physics

Japanese physicists devise technology to discover axion dark matter.

Sep 23, 2019

Return to the Moon? 3D Printing with Moondust Could Be the Key to Future Lunar Living

Posted by in categories: 3D printing, space travel

This article was originally published at The Conversation. The publication contributed the article to Space.com’s Expert Voices: Op-Ed & Insights.

The entire Apollo 11 mission to the moon took just eight days. If we ever want to build permanent bases on the moon, or perhaps even Mars or beyond, then future astronauts will have to spend many more days, months and maybe even years in space without a constant lifeline to Earth. The question is how would they get hold of everything they needed. Using rockets to send all the equipment and supplies for building and maintaining long-term settlements on the moon would be hugely expensive.

This is where 3D printing could come in, allowing astronauts to construct whatever their lunar colony needed from raw materials. Much of the excitement around 3D printing in space has focused on using it to construct buildings from lunar rock. But my research suggests it may actually be more practical to use this moondust to supply lunar manufacturing labs turning out replacement components for all sorts of equipment.

Sep 23, 2019

Atoms spin backward while flying along a surface

Posted by in category: particle physics

Atoms experience a kind of rolling friction when they fly along a surface.

Sep 23, 2019

Scientists Were Wrong About DNA – It Is Actually Held Together

Posted by in category: biotech/medical

Researchers at Chalmers University of Technology, Sweden, disprove the prevailing theory of how DNA binds itself. It is not, as is generally believed, hydrogen bonds which bind together the two sides of the DNA structure. Instead, water is the key. The discovery opens doors for new understanding in research in medicine and life sciences. The researchers’ findings are presented in the journal PNAS.

DNA is constructed of two strands, consisting of sugar molecules and phosphate groups. Between these two strands are nitrogen bases, the compounds which make up organisms’ genes, with hydrogen bonds between them. Until now, it was commonly thought that those hydrogen bonds were what held the two strands together.

But now, researchers from Chalmers University of Technology show that the secret to DNA’s helical structure may be that the molecules have a hydrophobic interior, in an environment consisting mainly of water. The environment is therefore hydrophilic, while the DNA molecules’ nitrogen bases are hydrophobic, pushing away the surrounding water. When hydrophobic units are in a hydrophilic environment, they group together, to minimize their exposure to the water.

Sep 23, 2019

A Child’s Puzzle Has Helped Unlock the Secrets of Magnetism

Posted by in category: physics

People have known about magnets since ancient times, but the physics of ferromagnetism remains a mystery. Now a familiar puzzle is getting physicists closer to the answer.

Sep 23, 2019

Roboethics: The Human Ethics Applied to Robots

Posted by in categories: ethics, robotics/AI

Roboethics wants to answer the question of who or what is going to be held responsible for the actions of the robotic creations of engineers and designers until robots become moral actors, if that ever happens.