Navigation Links
Researchers measure elusive repulsive force from quantum fluctuations
Date:1/7/2009

CAMBRIDGE, Mass. January 7, 2008 Researchers from Harvard University and the National Institutes of Health (NIH) have measured, for the first time, a repulsive quantum mechanical force that could be harnessed and tailored for a wide range of new nanotechnology applications.

The study, led by Federico Capasso, Robert L. Wallace Professor of Applied Physics at Harvard's School of Engineering and Applied Science (SEAS), will be published as the January 8 cover story of Nature.

The discovery builds on previous work related to what is called the Casimir force. While long considered only of theoretical interest, physicists discovered that this attractive force, caused by quantum fluctuations of the energy associated with Heisenberg's uncertainty principle, becomes significant when the space between two metallic surfaces, such as two mirrors facing one another, measures less than about 100 nanometers.

"When two surfaces of the same material, such as gold, are separated by vacuum, air, or a fluid, the resulting force is always attractive," explained Capasso.

Remarkably, but in keeping with quantum theory, when the scientists replaced one of the two metallic surfaces immersed in a fluid with one made of silica, the force between them switched from attractive to repulsive. As a result, for the first time, Capasso and his colleagues measured what they have deemed a repulsive Casimir.

To measure the repulsive force, the team immersed a gold coated microsphere attached to a mechanical cantilever in a liquid (bromobenzene) and measured its deflection as the distance from a nearby silica plate was varied.

"Repulsive Casimir forces are of great interest since they can be used in new ultra-sensitive force and torque sensors to levitate an object immersed in a fluid at nanometric distances above a surface. Further, these objects are free to rotate or translate relative to each other with minimal static friction because their surfaces never come into direct contact," said Capasso.

By contrast, attractive Casimir forces can limit the ultimate miniaturization of small-scale devices known as Micro Electromechanical Systems (MEMS), a technology widely used to trigger the release of airbags in cars, as the attractive forces may push together moving parts and render them inoperable, an effect known as stiction.

Potential applications of the team's finding include the development of nanoscale-bearings based on quantum levitation suitable for situations when ultra-low static friction among micro- or nano-fabricated mechanical parts is necessary. Specifically, the researchers envision new types of nanoscale compasses, accelerometers, and gyroscopes.


'/>"/>

Contact: Michael Patrick Rutter
mrutter@seas.harvard.edu
617-496-3815
Harvard University
Source:Eurekalert  

Related biology technology :

1. Researchers improve ability to write and store information on electronic devices
2. Long-awaited international ethical guidelines for biobank researchers
3. CU researchers shed light on light-emitting nanodevice
4. Stevens researchers provide new information about mass spectrometry
5. Researchers measure carbon nanotube interaction
6. Researchers underscore limitations of genetic ancestry tests
7. ASU researchers improve memory devices using nanotech
8. UD researchers race ahead with latest spintronics achievement
9. Researchers outline structure of largest nonvirus particle ever crystallized
10. Ames Laboratory researchers solve fuel-cell membrane structure conundrum
11. Researchers use magnetism to target cells to animal arteries
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Researchers measure elusive repulsive force from quantum fluctuations
(Date:6/23/2016)... , June 23, 2016 /PRNewswire/ - FACIT ... Ontario biotechnology company, Propellon Therapeutics ... development and commercialization of a portfolio of first-in-class ... Epigenetic targets such as WDR5 represent an exciting ... significantly in precision medicine for cancer patients. Substantial ...
(Date:6/23/2016)... YORK , June, 23, 2016  The Biodesign ... to envision new ways to harness living systems and ... Modern Art (MoMA) in New York City ... than 130 participating students, showcased projects at MoMA,s Celeste ... Paola Antonelli , MoMA,s senior curator of architecture ...
(Date:6/23/2016)... , June 23, 2016 Apellis Pharmaceuticals, ... 1 clinical trials of its complement C3 inhibitor, ... and multiple ascending dose studies designed to assess ... of subcutaneous injection in healthy adult volunteers. ... either as a single dose (ranging from 45 ...
(Date:6/23/2016)... WI (PRWEB) , ... June 23, 2016 , ... ... focused on quality, regulatory and technical consulting, provides a free webinar ... presented on July 13, 2016 at 12pm CT at no charge. , Incomplete ...
Breaking Biology Technology:
(Date:4/13/2016)... 13, 2016  IMPOWER physicians supporting Medicaid patients in ... new clinical standard in telehealth thanks to a new ... higi platform, IMPOWER patients can routinely track key health ... mass index, and, when they opt in, share them ... to a local retail location at no cost. By ...
(Date:3/31/2016)... -- Genomics firm Nabsys has completed a financial  restructuring under ... M.D., who returned to the company in October 2015. ... including Chief Technology Officer, John Oliver , Ph.D., ... Vice President of Software and Informatics, Michael Kaiser ... Bready served as CEO of Nabsys from 2005-2014 and ...
(Date:3/23/2016)... 2016 Einzigartige ... und Stimmerkennung mit Passwörtern     ... MESG ), ein führender Anbieter digitaler Kommunikationsdienste, ... SpeechPro zusammenarbeitet, um erstmals dessen Biometrietechnologie einzusetzen. ... Möglichkeit angeboten, im Rahmen mobiler Apps neben ...
Breaking Biology News(10 mins):