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Metamaterials
Updated April
3, 2007
Click
here to go to our main page on microwave materials
New for April 2007! It's
about time we weighed in on the subject of metamaterials, even if
we don't know a heckuva lot about them. How about some help here?
Metamaterials are a class of
artificial material structures comprised of patterned metals and
dielectric layers. Metal features are small compared to wavelength,
and the features are periodic.
By carefully engineering the
structure, a negative index of refraction can occur at specific
frequencies. Looking at this another way, the Poynting vector no
longer obeys the right-hand rule; this is what give metamaterials
the nickname "left-handed materials". Note that negative
refraction is not the equivalent of perpetual motion, it
just means that EM energy bends in the opposite direction you'd
think it would when it encounters left-handedness.
What can we do with this new
class of materials at microwave frequencies? The number one suggestion
for microwave application is as stealth technology, or in words
James T. Kirk would understand, as a cloaking device. But the utility
of such a device is expected to be limited, it might only spoof
your enemies if they used a specific frequency and illuminated your
hardware at a specific angle. There might also be some interesting
ways to use metamaterials in antennas. Optical metamaterials might
have a bright future in Las Vegas, as part of a magic act. Now you
see it, now you don't!
Let's give metamaterials the
benefit of the doubt, and we won't list the technology on our career-killer
page. Yet.
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