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Graphene-based Nanoantennas Could Allow WLANs of Nanodevices
Freshly Exhumed writes "With the onslaught of graphene experimentation, especially in computing and RF, news from IEEE Spectrum comes that researchers at Georgia Tech have computer-modeled nanoantennas made from graphene that could provide wireless network communications between nanoscopic devices. "We are exploiting the peculiar propagation of electrons in graphene to make a very small antenna that can radiate at much lower frequencies than classical metallic antennas of the same size," said Ian Akyildiz, a professor at the Georgia Institute of Technology, in a press release. "We believe that this is just the beginning of a new networking and communications paradigm based on the use of graphene.""
A use I could think of is having these embedded into thread, and then stitched into regular clothing. I'd imagine our bodies generate enough residual energy to power it and they would act as a cumulative network that could broadcast your vitals to a external device.
Restore the madness of youth's lechery
"We are exploiting the peculiar propagation of electrons in graphene to make a very small antenna that can radiate at much lower frequencies than classical metallic antennas of the same size," said Ian Akyildiz, a professor at the Georgia Institute of Technology, in a funding drive.
FTFY.
systemd is Roko's Basilisk.
Can you imagine trying to rig up a patch panel for these nano devices?
I deny that I have not avoided attaining the opposite of that which I do not want.
The graphic at the top of the article indicates 10-100 nm. This is out in the UV, and would make a quite horrible wireless system. The article mentions terahertz, which would be 10-100 um. Still only useable over short distances, but much more likely.
The relevant xkcd
I would read Greg Bear's "Blood Music" -- I think you're ready for it.
Do not mock my vision of impractical footwear
Nano is 10^-9. Nanoscale means just that.
Actually everything below 10^-6 is called "nano" (because e.g. 10^-7 is 100 nano — and, of course, because that way you can label your stuff "nano" much earlier ;-)).
The Tao of math: The numbers you can count are not the real numbers.
This fool has never studied SI prefixes which the GP is obviously referring to.
I know SI prefixes very well.
10^-3 = milli
10^-6 = micro
10^-9 = nano.
10^-7 = 10^(2-9) = 10^2 * 10^-9 = 100 nano
Advice to AC: Learn your power laws.
The Tao of math: The numbers you can count are not the real numbers.
Well, if pot and kettle get WiFi enabled, then finally the pot can really call the kettle black. ;-)
The Tao of math: The numbers you can count are not the real numbers.
Billions of nanobots spread in the air, capable of audio/video streaming... now that would be "1984" on steroids. Think of NSA being able to look anywhere at any time, live.
839*929
The 10-100 nm dimension is transverse to the surface plasmon; the length of antenna is shown as 1 m. In the same way as the width of the wire you build your radio aerial isn't really relevant to reception but the length is, the 10-100 nm dimension isn't particularly relevant to this little device's behaviour.
There's still a problem of length scales here in that the 0.1-10 THz claimed has much longer wavelengths than this 1 m device -- I don't know what the refractive index (or more strictly, the dielectric) of graphene is but I'd be surprised if it were in the 100-1000 range that is required to do this with traditional plasmonics. But that's the entire point of the article... their models have predicted something that is not expected from the classical electrodynamics that /. readers (think they) remember from 1st year physics and so want to apply to everything that ever goes past. Now if only the university's press office had waited for the research to be published rather than sending out the press release with the vague "the research is scheduled to be reported in the journal IEEE JSAC" we'd actually be able to look at it and learn. I assume I'll see it in a Table of Contents alert in a month or two and actually read it then. Yay. (It's also a very odd choice of journal to publish this sort of work so we may yet find that the journal article has little to do with the press release at all.)
And I'm a leaker.
That's what sanitary pads are for, you know.
I've seen many types of graphene antennas built and tested over the last several years.
The resistivity of very high quality graphene is about 1000 ohms per square. Any advantage you may get from graphene is offset by huge impedance losses. You're looking at 10 to 100 kOhm resistance for the antennas described in the article. That's simply not going to work in a realistic system, particularly one based around an electrically small antenna.
The physics of antennas is pretty darn basic electrodynamics. You need a quarter to half a wavelength to make an efficient antenna. Scientists and engineers have tried for well over a century to overcome that limitation, with not much success. It's pretty basic-- if you want to set up an EM field, you need to be able to have charges separated by a goodly amount relative to the wavelength. The emitting material is irrelevant, in fact you need a really good conductor as you make the antenna shorter, as it's radiation resistance goes way down with length. Gaphene not only does not seem to have any advantage, it's high resistance is a big disadvantage. Sounds super highly fishy.
Yes, a definitely good read.