- Number 300 |
- November 23, 2009
Harnessing the Casimir Effect
Nanoscale machines used in medicine and other fields may someday operate more efficiently thanks to recent discoveries by researchers at DOE’s Ames Laboratory. The research uses an exotic class of materials known as chiral metamaterials that can harness the so-called Casimir effect.
Dutch physicist Hendrik Casimir theorized that if you place two objects such as plates close to one another inside a vacuum, the longer wavelengths of the electromagnetic field present would be blocked, since they couldn’t fit between the small gap separating the plates. The amount of energy density inside the gap decreases as the gap gets smaller. So work has to be done to pull the plates apart. As a consequence, an attractive force exists that prompts the plates to come closer together and in nanoscale environments this force is strong enough to cause tiny devices to permanently lock up.
The Ames Laboratory researchers, led by senior physicist Costas Soukoulis, is using chiral metamaterials to exert a repulsive force capable of pushing the two plates apart. The results were published in the September 4, 2009 issue of Physical Review Letters, in an article entitled, “Repulsive Casimir Force in Chiral Metamaterials.”
[Mark Ingebretsen, 515.294.3474,