Surface waves can help nanostructured devices keep their cool — ScienceDaily

The continuing progress in miniaturization of silicon microelectronic and photonic devices is causing cooling of the device structures to become increasingly challenging. Conventional heat transport in bulk materials is dominated by acoustic phonons, which are quasiparticles that represent the material’s lattice vibrations, similar to the way that photons represent light waves. Unfortunately, this type of cooling is reaching its limits in these tiny structures.

However, surface effects become dominant as the materials in nanostructured devices become thinner, which means that surface waves may provide the thermal transport solution required. Surface phonon-polaritons (SPhPs) — hybrid waves composed of surface electromagnetic waves and optical phonons that propagate along the surfaces of dielectric membranes — have shown particular promise, and a team led by researchers from the Institute of Industrial Science, the University of Tokyo has now demonstrated and verified the thermal conductivity enhancements provided by these waves.

“We generated SPhPs on silicon

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Marine Heat Waves Are Putting Caribbean Fisheries In Hot Water

Small-scale fisheries are a critical component of the social and economic and fabric of coastal communities in the Caribbean and are key to the region’s food security, with annual fish consumption ranging between 10 and 35 kg/capita per year (FAO, 2014). But marine heat waves (MHW) or extended periods of anomalously warm ocean temperatures1 can have major impacts on marine biodiversity and ecosystems, and are a significant threat to the regional fisheries sector. A 2019 study in journal, Nature Climate Change, reports that coral reefs in the Caribbean have been among the hardest hit by heat waves, and the Food and Agriculture Organisation has found that the Caribbean fisheries sector is most vulnerable to climate change in the world. (Monnereau, 2017)

According to a September article in journal, Science, as global warming makes oceans hotter, marine heat waves (MHW) have become at least 20 times more likely. “The duration,

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Severe marine heat waves linked to human-caused warming

Unusually hot zones in the ocean likely will become longer, more frequent.

This is an Inside Science story.

The scientists, led by postdoctoral researcher Charlotte Laufkötter at the University of Bern in Switzerland, focused on seven well-documented marine heat waves from the past decade. For each hot spell, they calculated the relative probabilities that a similar event could have occurred with and without human influence. They found that human activities such as greenhouse gas emissions made the heat waves much more likely

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Seismic sound waves crossing the deep ocean could be a new thermometer

A seismometer on the atoll of Diego Garcia (left) can calculate ocean temperature with earthquakes near Sumatra (right).
Enlarge / A seismometer on the atoll of Diego Garcia (left) can calculate ocean temperature with earthquakes near Sumatra (right).

Geophysics has shown that precise measurements and a little modeling can perform wonders, like showing us the detailed structure of the Earth’s interior despite the fact that it is inaccessibly buried beneath hundreds of kilometers of rock. This is possible because seismic waves produced by earthquakes subtly change velocity or direction as they pass through different materials. A new paper shows that something similar can actually measure small temperature changes in the deep ocean.

An idea to use acoustic waves from man-made sources was actually floated several decades ago but died out after some trials. A team led by Wenbo Wu at the University of Toronto realized that earthquakes could be taken advantage of in the same way, removing the expensive logistics of constantly setting off booms to get

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Why We’re Scared of Invisible Radio Waves

This article originally appeared on VICE France.

The 5G rollout has been far from smooth. Despite its dazzling promises, like the advent of self-driving cars and virtual reality, the fifth generation of mobile internet is considered a threat by many. On the 14th of July of this year, the UK banned 5G kits produced by Chinese manufacturer Huawei due to security concerns. Meanwhile, activists are taking issue with the environmental cost of the new technology, which will require enormous resources just to replace the already-speedy 4G network.

Then, there’s a group of people who oppose 5G because they believe it’s a health hazard. The theory that mobile phones cause cancer has been around for a while, albeit with little scientific basis. In its latest iteration, conspiracy theorists say 5G phone towers are weakening our immune systems and increasing our vulnerability to COVID-19. Some even believe the towers transmit the

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