Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button

Home > Press > Metamaterials could reduce friction in nanomachines

Abstract:
Ames Laboratory researchers discover repulsive Casimir effect

Metamaterials could reduce friction in nanomachines

Ames, IA | Posted on December 29th, 2009

Nanoscale machines expected to have wide application in industry, energy, medicine and other fields may someday operate far more efficiently thanks to important theoretical discoveries concerning the manipulation of famous Casimir forces that took place at the U.S. Department of Energy's Ames Laboratory.

The groundbreaking research, conducted through mathematical simulations, revealed the possibility of a new class of materials able to exert a repulsive force when they are placed in extremely close proximity to each other. The repulsive force, which harnesses a quantum phenomenon known as the Casimir effect, may someday allow nanoscale machines to overcome mechanical friction.

Though the frictional forces in nanoscale environments are small, they significantly inhibit the function of the tiny devices designed to operate in that realm, explained Costas Soukoulis, a senior physicist at the Ames Lab and Distinguished Professor of physics at Iowa State University, who led the research effort.

Soukoulis and his teammates, including Ames Laboratory assistant scientist Thomas Koschny, were the first to study the use of exotic materials known as chiral metamaterials as a way to harness the Casimir effect. Their efforts have demonstrated that it is indeed possible to manipulate the Casimir force. The findings were published in the Sept. 4, 2009 issue of Physical Review Letters, in an article entitled, "Repulsive Casimir Force in Chiral Metamaterials."

Understanding the importance of their discovery requires a basic understanding of both the Casimir effect and the unique nature of chiral metamaterials.

The Casimir effect was named after Dutch physicist Hendrik Casimir, who postulated its existence in 1948. Using quantum theory, Casimir predicted that energy should exist even in a vacuum, which can give rise to forces acting on the bodies brought into close proximity of each other. For the simple case of two parallel plates, he postulated that the energy density inside the gap should decrease as the size of the gap decreases, also meaning work must be done to pull the plates apart. Alternatively, an attractive force that pushes the plates closer together can be said to exist.

Casimir forces observed experimentally in nature have almost always been attractive and have rendered nanoscale and microscale machines inoperable by causing their moving parts to permanently stick together. This has been a long-standing problem that scientists working on such devices have struggled to overcome.

Remarkably, this new discovery demonstrates that a repulsive Casimir effect is possible using chiral metamaterials. Chiral materials share an interesting characteristic: their molecular structure prevents them from being superimposed over a reverse copy of themselves, in the same way a human hand cannot fit perfectly atop a reverse image of itself. Chiral materials are fairly common in nature. The sugar molecule (sucrose) is one example. However, natural chiral materials are incapable of producing a repulsive Casimir effect that is strong enough to be of practical use.

For that reason, the group turned its attention to chiral metamaterials, so named because they do not exist in nature and must instead be made in the lab. The fact that they are artificial gives them a unique advantage, commented Koschny. "With natural materials you have to take what nature gives you; with metamaterials, you can create a material to exactly meet your requirements," he said.

The chiral metamaterials the researchers focused on have a unique geometric structure that enabled them to change the nature of energy waves, such as those located in the gap between the two closely positioned plates, causing those waves to exert a repulsive Casimir force.

The present study was carried out using mathematical simulations because of the difficulties involved in fabricating these materials with semiconductor lithographic techniques. While more work needs to be done to determine if chiral materials can induce a repulsive Casimir force strong enough to overcome friction in nanoscale devices, practical applications of the Casimir effect are already under close study at other DOE facilities, including Los Alamos and Sandia national laboratories. Both have expressed considerable interest in using the chiral metamaterials designed at Ames Laboratory to fabricate new structures and reduce the attractive Casimir force, and possibly to obtain a repulsive Casimir force.

Funding for this research was provided by the DOE Office of Science.

####

About Ames Laboratory
Ames Laboratory is a U.S. Department of Energy Office of Science research facility operated by Iowa State University. Ames Laboratory creates innovative materials, technologies and energy solutions. We use our expertise, unique capabilities and interdisciplinary collaborations to solve global challenges.

For more information, please click here

Contacts:
Mark Ingebretsen

515-294-3474

Copyright © Eurekalert

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Scientists change properties of zeolites to improve hemodialysis July 29th, 2016

Novel state of matter: Observation of a quantum spin liquid July 29th, 2016

A new type of quantum bits July 29th, 2016

Lonely atoms, happily reunited July 29th, 2016

Physics

Novel state of matter: Observation of a quantum spin liquid July 29th, 2016

A new type of quantum bits July 29th, 2016

NEMS

Integration of novel materials with silicon chips makes new 'smart' devices possible July 25th, 2016

Nano-photonics meets nano-mechanics: Controlling on-chip nano-optics by graphene nano-opto-mechanics January 22nd, 2016

Mechanical quanta see the light January 20th, 2016

Nanodevices at one-hundredth the cost: New techniques for building microelectromechanical systems show promise December 20th, 2015

Govt.-Legislation/Regulation/Funding/Policy

A new type of quantum bits July 29th, 2016

Thomas Swan and NGI announce unique partnership July 28th, 2016

Penn team uses nanoparticles to break up plaque and prevent cavities July 28th, 2016

Beating the heat a challenge at the nanoscale: Rice University scientists detect thermal boundary that hinders ultracold experiments July 28th, 2016

Possible Futures

Scientists change properties of zeolites to improve hemodialysis July 29th, 2016

Novel state of matter: Observation of a quantum spin liquid July 29th, 2016

A new type of quantum bits July 29th, 2016

Pixel-array quantum cascade detector paves the way for portable thermal imaging devices: Research team from TU-Wien Center for Micro- and Nanostructures have developed a new 'cooler' sensing instrument thereby increasing energy-efficiency and enhancing mobility for diagnostic tes July 28th, 2016

MEMS

Integration of novel materials with silicon chips makes new 'smart' devices possible July 25th, 2016

New research unveils graphene 'moth eyes' to power future smart technologies: New ultra-thin, patterned graphene sheets will be essential in designing future technologies such as 'smart wallpaper' and Internet-of-things applications March 1st, 2016

Vesper Collaborates with GLOBALFOUNDRIES to Deliver First Piezoelectric MEMS Microphones: Acoustic sensing company works with top foundry to support mass-market consumer products January 21st, 2016

MEMS & Sensors Industry Group Previews “Internet of MEMS & Sensors” at CES 2016 -- Global industry association invites CE OEMS/integrators to conference track on January 7 January 6th, 2016

Molecular Machines

New remote-controlled microrobots for medical operations July 23rd, 2016

Pushing a single-molecule switch: An international team of researchers from Donostia International Physics Center, Fritz-Haber Institute of the Max Planck Society, University of Liverpool, and the Polish Academy of Sciences has shown a new way to operate a single-molecule switch July 19th, 2016

Researchers harness DNA as the engine of super-efficient nanomachine: New platform detects traces of everything from bacteria to viruses, cocaine and metals July 10th, 2016

On the path toward molecular robots: Scientists at Japan's Hokkaido University have developed light-powered molecular motors that repetitively bend and unbend, bringing us closer to molecular robots. July 8th, 2016

Materials/Metamaterials

Scientists change properties of zeolites to improve hemodialysis July 29th, 2016

Lonely atoms, happily reunited July 29th, 2016

WSU researchers 'watch' crystal structure change in real time: Breakthrough made possible by new Argonne facility July 27th, 2016

New lithium-oxygen battery greatly improves energy efficiency, longevity: New chemistry could overcome key drawbacks of lithium-air batteries July 26th, 2016

Announcements

Scientists change properties of zeolites to improve hemodialysis July 29th, 2016

Novel state of matter: Observation of a quantum spin liquid July 29th, 2016

A new type of quantum bits July 29th, 2016

Lonely atoms, happily reunited July 29th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic