Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New colossal carbon tubes created, and flipping spins at the speed limit

31.07.2008
Colossal Carbon Tubes leave Kevlar and Nanotubes in the Dust H. Peng, D. Chen, J.-Y. Huang, S. B. Chikkannanavar, J. Hänisch, M. Jain, D. E. Peterson, S. K. Doorn, Y. Lu, Y. T. Zhu, and Q. X. Jia Physical Review Letters (forthcoming)

A collaboration of Chinese and American physicists has discovered a way to make a new carbon structure that could lead to fabrics 30 times stronger than Kevlar and 224 times stronger than cotton. The group dubbed the structures colossal carbon tubes because they're thousands of times larger than carbon nanotubes. At 40-100 millionths of a meter across and centimeters long, they're comparable in size to typical cotton fibers.

The structures consist of nested inner and outer tubes separated by hollow channels, making the tubes both light and strong. While they are nowhere near as strong as carbon nanotubes, the colossal tubes are much more ductile than the nanoscopic variety, making them more suited for spinning into threads and weaving into fabrics. The colossal tubes conduct electricity and show some of the properties of semiconductors, which means that they could lead to novel microelectronic components as well as super strong cloth.

The details regarding how the intricate structures form is still hazy, but the researchers propose that colossal carbon tubes could be incorporated into improved body armor, stronger carbon fiber composites (which are often shaped into parts for high-performance and lightweight vehicles), or components in microelectronics and tiny machines.

Spin Flips Hit the Speed Limit
S. Serrano-Guisan, K. Rott, G. Reiss, J. Langer, B. Ocker, and H.W. Schumacher Physical Review Letters (forthcoming)

A team of physicists at Physikalisch-Technische Bundesanstalt in Germany has managed to flip a nanoscopic magnet as fast as the fundamental speed limit allows. Their experiment consisted of two stacked layers of tiny magnets separated by a thin barrier to form what is called a magnetic tunnel junction. Such magnetic tunneling junctions are promising candidates for future magnetic memory chips.

The researchers allowed electrons aligned in a special way to flow between the layers, developing a spin torque, or twisting force that is transferred from one layer of nanomagnet onto the other. This torque pumps enough energy to the nanomagnet to make it move faster and faster until it changes direction. Several measurements showed that the researchers were able to switch the direction of magnetization as fast as physically possible.

Their spin torque record is important for the next generation of low current, ultra fast magnetic memory chips and sensors. This new generation of electronics encodes information in an electronic spin, rather than in an electronic charge. The spin torque switching effect is a powerful new approach to controlling electronic spins.

James Riordon | American Physical Society
Further information:
http://www.aps.org

More articles from Physics and Astronomy:

nachricht LIGO confirms RIT's breakthrough prediction of gravitational waves
12.02.2016 | Rochester Institute of Technology

nachricht Milestone in physics: gravitational waves detected with the laser system from LZH
12.02.2016 | Laser Zentrum Hannover e.V.

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Production of an AIDS vaccine in algae

Today, plants and microorganisms are heavily used for the production of medicinal products. The production of biopharmaceuticals in plants, also referred to as “Molecular Pharming”, represents a continuously growing field of plant biotechnology. Preferred host organisms include yeast and crop plants, such as maize and potato – plants with high demands. With the help of a special algal strain, the research team of Prof. Ralph Bock at the Max Planck Institute of Molecular Plant Physiology in Potsdam strives to develop a more efficient and resource-saving system for the production of medicines and vaccines. They tested its practicality by synthesizing a component of a potential AIDS vaccine.

The use of plants and microorganisms to produce pharmaceuticals is nothing new. In 1982, bacteria were genetically modified to produce human insulin, a drug...

Im Focus: The most accurate optical single-ion clock worldwide

Atomic clock experts from the Physikalisch-Technische Bundesanstalt (PTB) are the first research group in the world to have built an optical single-ion clock which attains an accuracy which had only been predicted theoretically so far. Their optical ytterbium clock achieved a relative systematic measurement uncertainty of 3 E-18. The results have been published in the current issue of the scientific journal "Physical Review Letters".

Atomic clock experts from the Physikalisch-Technische Bundesanstalt (PTB) are the first research group in the world to have built an optical single-ion clock...

Im Focus: Goodbye ground control: autonomous nanosatellites

The University of Würzburg has two new space projects in the pipeline which are concerned with the observation of planets and autonomous fault correction aboard satellites. The German Federal Ministry of Economic Affairs and Energy funds the projects with around 1.6 million euros.

Detecting tornadoes that sweep across Mars. Discovering meteors that fall to Earth. Investigating strange lightning that flashes from Earth's atmosphere into...

Im Focus: Flow phenomena on solid surfaces: Physicists highlight key role played by boundary layer velocity

Physicists from Saarland University and the ESPCI in Paris have shown how liquids on solid surfaces can be made to slide over the surface a bit like a bobsleigh on ice. The key is to apply a coating at the boundary between the liquid and the surface that induces the liquid to slip. This results in an increase in the average flow velocity of the liquid and its throughput. This was demonstrated by studying the behaviour of droplets on surfaces with different coatings as they evolved into the equilibrium state. The results could prove useful in optimizing industrial processes, such as the extrusion of plastics.

The study has been published in the respected academic journal PNAS (Proceedings of the National Academy of Sciences of the United States of America).

Im Focus: New study: How stable is the West Antarctic Ice Sheet?

Exceeding critical temperature limits in the Southern Ocean may cause the collapse of ice sheets and a sharp rise in sea levels

A future warming of the Southern Ocean caused by rising greenhouse gas concentrations in the atmosphere may severely disrupt the stability of the West...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Symposium on Climate Change Adaptation in Africa 2016

12.02.2016 | Event News

Travel grants available: Meet the world’s most proficient mathematicians and computer scientists

09.02.2016 | Event News

AKL’16: Experience Laser Technology Live in Europe´s Largest Laser Application Center!

02.02.2016 | Event News

 
Latest News

LIGO confirms RIT's breakthrough prediction of gravitational waves

12.02.2016 | Physics and Astronomy

Gene switch may repair DNA and prevent cancer

12.02.2016 | Life Sciences

Using 'Pacemakers' in spinal cord injuries

12.02.2016 | Medical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>