From: Spudboy100@aol.com
Date: Sun Apr 06 2003 - 01:39:58 MST
http://www.spectrum.ieee.org/WEBONLY/newslog/index.html#s1
3 April 2003
Flat lens bends laws of physics
A University of Toronto researcher is bending far more than light in his new
lenses, he’s bending the laws of physics. George Eleftheriades, an associate
professor of electrical and computer engineering, has shown experimentally
that a flat lens built out of a strange class of materials can actually focus
light with better resolution than conventional lenses. His latest results
about the lens are to be published in the 7 April issue of Optics Express,
and its focusing ability was reported in the 24 March issue of Applied
Physics Letters.
Normally, a lens has to be curved to focus light, but Eleftheriades showed
that you can do the same with a flat lens made out of an artificially created
material that bends light the wrong way—a flat lens normally would disperse
light, but made of a novel "left-handed" material, it actually focuses it.
"If you say you can invert the laws of refraction, it’s really a bold
proposition. It’s really new physics," Eleftheriades told IEEE Spectrum. So
new, in fact, that last December scientists were still debating about whether
left-handed materials even existed, let alone whether they could focus light.
But Eleftheriades demonstrated that his material could and published his work
in the December 2002 issue of IEEE Transactions of Microwave Theory and
Techniques. The 7 April paper confirms and refines his previous results.
This seemingly abstract concept could have some very concrete potential.
Anything smaller than a wavelength of light, such as atoms and molecules are
out of reach for even the best optical microscopes. In his 24 March paper,
Eleftheriades presented simulations that showed that his lens can focus and
amplify the tiny "subwaves" that carry information about smaller objects.
Because the resolution is lower than the wavelength of light, such a lens
would let scientists literally see previously invisible objects like atoms.
It could also focus light into an area smaller than its wavelength creating
sharp beams that could be used to burn more information onto CDs or etch more
tightly packed features onto semiconductor chips. The lens could similarly
focus RF waves to enhance the bandwidth on cell phones and make more
effective antennas.
For background on left-handed materials, see {novel Optical Material could
Mean Sharper Lithography," by Justin Mullin, IEEE Spectrum, January 2001, pp.
25-27.
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