Feeds

Unexpected nanotube heat transfer suggests new way to cool processors

Spooky action at a (small) distance

Intelligent flash storage arrays

A strange phenomenon observed at the University of Maryland could pave the way to new techniques for cooling electronics: when researchers passed a current through carbon nanotubes, they didn’t heat up – but other nearby objects did.

While still studying exactly what mechanism produces the phenomenon, the researchers report that when they passed a current through the carbon nanotubes, the tubes remained relatively cool, apparently transferring the heat directly to the silicon nitride substrate that hosted the tubes.

In what they’ve dubbed “remote Joule heating”, the scientists, led by then-student Kamal Baloch, found that the heating of the substrate was enough to melt metal particles on its surface.

The normal heating of metals carrying a current, Joule heating, happens when energy is transferred from the travelling electrons to the atoms in the wire, causing them to vibrate.

In the University of Maryland experiment, the researchers believe the transfer of heat from the carbon nanotubes to the substrate is being caused not by the direct contact of electrons colliding with atoms, but rather by electrical fields.

“We believe that the nanotube's electrons are creating electrical fields due to the current, and the substrate's atoms are directly responding to those fields,” says assistant professor John Cumings.

“The transfer of energy is taking place through these intermediaries, and not because the nanotube's electrons are bouncing off of the substrate's atoms. While there is some analogy to a microwave oven, the physics behind the two phenomena is actually very different.”

The observations were made using a technique called electron thermal microscopy, developed in Cumings’ laboratory, which maps where heat is generated in nanoscale devices.

Baloch says the phenomenon would be useful in semiconductor design, because it provides a way to design thermal properties independently of the electrical properties of a device. “This new mechanism of thermal transport would allow you to engineer your thermal conductor and electrical conductor separately, choosing the best properties for each without requiring the two to be the same material occupying the same region of space,” he said.

The next step in the research is to see what other materials might exhibit similar behavior. The research is published in Nature Nanotechnology, abstract here. ®

Providing a secure and efficient Helpdesk

More from The Register

next story
GRAV WAVE DRAMA: 'Big Bang echo' may have been grit on the scanner – boffins
Exit Planet Dust on faster-than-light expansion of universe
SpaceX Dragon cargo truck flies 3D printer to ISS: Clawdown in 3, 2...
Craft berths at space station with supplies, experiments, toys
That glass of water you just drank? It was OLDER than the SUN
One MEELLION years older. Some of it anyway
NASA rover Curiosity drills HOLE in MARS 'GOLF COURSE'
Joins 'traffic light' and perfect stony sphere on the Red Planet
Big dinosaur wowed females with its ENORMOUS HOOTER
That's right, Doris, I've got biggest snout in the prehistoric world
Japanese volcano eruption reportedly leaves 31 people presumed dead
Hopes fade of finding survivors on Mount Ontake
Relive the death of Earth over and over again in Extinction Game
Apocalypse now, and tomorrow, and the next day, and the day after that ...
prev story

Whitepapers

A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Beginner's guide to SSL certificates
De-mystify the technology involved and give you the information you need to make the best decision when considering your online security options.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.