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Primeur weekly 2015-06-01

The Cloud

Registration opens for ISC Cloud & Big Data ...

EMC to acquire Virtustream ...

EuroFlash

Snapwallet: a safe photo service for smart phone ...

Dutch Government plans 135 million euro funding for supercomputers ...

Tackling the fastest and most powerful computing systems on the planet ...

Understanding and controlling the propagation of waves ...

USFlash

Lawrence Livermore breaks ground on unclassified supercomputing facility ...

Silicon Mechanics announces recipients of 4th Annual Research Cluster Grant ...

RAPTOR turbulent combustion code selected for next-gen supercomputer readiness project ...

Cavium announces collaboration with Pegatron on server platforms based on Cavium's ThunderX workload optimized processor family ...

Ohio State University researchers prove magnetism can control heat and sound ...

OLCF names CAAR projects at IDC HPC User Forum ...

Physicists solve quantum tunneling mystery ...

Using the forest to see the trees ...

Tsinghua University crowned champions of 2015 ASC Student Supercomputer Challenge ...

OLCF shares Lustre knowledge at International Workshop ...

National Science Foundation extends the Kraken project ...

Woodside, Australia's largest independent oil and gas company, uses IBM Watson to enhance decision making and increase efficiencies ...

OLCF outreach projects garner awards ...

The first round of 2015 hackathons gets underway ...

Premier announces $21.6 million funding for Pawsey Supercomputing Centre ...

Fujitsu supports King Abdulaziz University research capabilities with new supercomputing system ...

Doctor Evidence brings valuable health data to IBM Watson ecosystem ...

SRC Computers launches Saturn 1 Server, the first reconfigurable hyperscale server ...

BG Brasil and Senai CIMATEC launch Latin America's fastest supercomputer ...

Ohio State University researchers prove magnetism can control heat and sound


Ohio State University
28 May 2015 Columbus - Phonons - the elemental particles that transmit both heat and sound - have magnetic properties, according to a landmark study supported by Ohio Supercomputer Center (OSC) services and recently published by a researcher group from the Ohio State University.

In a recent issue of the journalNature Materials, the researchers describe how a magnetic field, roughly the size of a medical MRI, reduced the amount of heat flowing through a semiconductor by 12 percent. Simulations performed at OSC then identified the reason for it - the magnetic field induces a diamagnetic response in vibrating atoms known as phonons, which changes how they transport heat.

"This adds a new dimension to our understanding of acoustic waves", stated Joseph Heremans, Ph.D., Ohio Eminent Scholar in Nanotechnology and a professor of mechanical engineering at Ohio State whose group performed the experiments. "We've shown that we can steer heat magnetically. With a strong enough magnetic field, we should be able to steer sound waves, too."

People might be surprised enough to learn that heat and sound have anything to do with each other, much less that either can be controlled by magnets, Joseph Heremans acknowledged. But both are expressions of the same form of energy, quantum mechanically speaking. So any force that controls one should control the other.

The nature of the effect of the magnetic field initially was not understood and subsequently was investigated through computer simulations performed on OSC's Oakley Cluster by Oscar Restrepo, Ph.D., a research associate, Nikolas Antolin, a doctoral student, and Wolfgang Windl, Ph.D., a professor, all of Ohio State's Department of Materials Science and Engineering. After painstakingly examining all possible magnetic responses that a non-magnetic material can have to an external field, they found that the effect is due to a diamagnetic response, which exists in all materials. This suggests then that the general effect should be present in any solid.

The implication: in materials such as glass, stone, plastic - materials which are not conventionally magnetic - heat can be controlled magnetically, if you have a powerful enough magnet. This development may have future impacts on new energy production processes.

But, there won't be any practical applications of this discovery any time soon: seven-tesla magnets like the one used in the study don't exist outside of hospitals and laboratories, and a semiconductor made of indium antimonide had to be chilled to -450 degrees Fahrenheit (-268 degrees Celsius) - very close to absolute zero - to make the atoms in the material slow down enough for the phonons' movements to be detectible.

To simulate the experiment, Wolfgang Windl and his computation team employed a quantum mechanical modeling strategy known as density functional theory (DFT). The DFT strategy was used to determine how the electron distribution changed when atoms vibrated with or without magnetic field. The motion of the electrons around their atoms changed in the field, creating diamagnetic moments when phonons were present. These moments then reacted to the field and slowed the heat transport, similar to an eddy current brake in a train.

The simulations were conducted on the Oakley Cluster, an HP/Intel Xeon system with more than 8,300 processor cores to provide researchers with a peak performance of 154 Teraflops - tech-speak for 154 trillion calculations per second. Since atoms can vibrate in many different ways, a large number of simulations were necessary, consuming approximately 1.5 million CPU hours even on a machine as powerful as Oakley. OSC engineers also helped the research team use OSC's high-throughput, parallel file system to handle the immense datasets generated by the DFT model.

"OSC offered us phenomenal support; they supported our compilation and parallel threading issues, helped us troubleshoot hardware issues when they arose due to code demands, and moved us to the Lustre high-performance file system after we jammed their regular file system", stated Nikolas Antolin, who is the expert for high-demand computations in Wolfgang Windl's group.

"Dr. Windl and his team are important OSC clients, and we're always pleased to support their research projects with our hardware, software and staff support services", stated David Hudak, Ph.D., OSC's director of supercomputer services. "With the addition of the Ruby Cluster this past fall and another, much more powerful system upcoming this fall, OSC will continue to offer even larger, faster and more powerful services to support this type of discovery and innovation."

Next, the group plans to test whether they can deflect sound waves sideways with magnetic fields.

Co-authors on the study included graduate student Hyungyu Jin and postdoctoral researcher Stephen Boona from mechanical and aerospace engineering; and Roberto Myers, Ph.D., an associate professor of materials science and engineering, physics and mechanical and aerospace engineering.

Funding for the study came from the U.S. Army Research Office, the U.S. Air Force Office of Scientific Research and the National Science Foundation (NSF), including funds from the NSF Materials Research Science and Engineering Center at Ohio State. Computing services were provided by the Ohio Supercomputer Center.
Source: Ohio Supercomputer Center - OSC

Back to Table of contents

Primeur weekly 2015-06-01

The Cloud

Registration opens for ISC Cloud & Big Data ...

EMC to acquire Virtustream ...

EuroFlash

Snapwallet: a safe photo service for smart phone ...

Dutch Government plans 135 million euro funding for supercomputers ...

Tackling the fastest and most powerful computing systems on the planet ...

Understanding and controlling the propagation of waves ...

USFlash

Lawrence Livermore breaks ground on unclassified supercomputing facility ...

Silicon Mechanics announces recipients of 4th Annual Research Cluster Grant ...

RAPTOR turbulent combustion code selected for next-gen supercomputer readiness project ...

Cavium announces collaboration with Pegatron on server platforms based on Cavium's ThunderX workload optimized processor family ...

Ohio State University researchers prove magnetism can control heat and sound ...

OLCF names CAAR projects at IDC HPC User Forum ...

Physicists solve quantum tunneling mystery ...

Using the forest to see the trees ...

Tsinghua University crowned champions of 2015 ASC Student Supercomputer Challenge ...

OLCF shares Lustre knowledge at International Workshop ...

National Science Foundation extends the Kraken project ...

Woodside, Australia's largest independent oil and gas company, uses IBM Watson to enhance decision making and increase efficiencies ...

OLCF outreach projects garner awards ...

The first round of 2015 hackathons gets underway ...

Premier announces $21.6 million funding for Pawsey Supercomputing Centre ...

Fujitsu supports King Abdulaziz University research capabilities with new supercomputing system ...

Doctor Evidence brings valuable health data to IBM Watson ecosystem ...

SRC Computers launches Saturn 1 Server, the first reconfigurable hyperscale server ...

BG Brasil and Senai CIMATEC launch Latin America's fastest supercomputer ...