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DARPA Creates 0.85 THz Solid State Receiver
hypnosec writes "DARPA, under its THz Electronics program, has designed a solid state receiver capable of THz (terahertz) frequencies thus inching towards the possibilities of transistor-based electronics that will operate at THz frequencies. The newly designed solid state receiver demonstrates a gain at 0.85 THz. This particular milestone is a stepping stone for the next target of 1.03 THz. Because of this achievement a host of DoD electronics capabilities can now be realized. One such application where this can be of use is for a sensor that will operate through clouds under a DARPA program dubbed VISAR."
This is Slashdot, not Wikipedia.
now we need to go OSS in diesel cars
I also have a THz wave receiver. It's called "eyes".
I also have this device capable of producing THz waves. It's a lamp.
Another terrible article summary.
In 2010, a solid-state device at 0.67THz was achieved. In 2012, that effort is up to 0.85 THz. Progress is slow, but continuing.
Diode-type CMOS imagers for terahertz radiation have been built. Those convert terahertz radiation into DC, which can then be amplified by standard techniques. But diodes don't have gain. That's why the original article emphasizes that this new device has gain.
There are terahertz lasers, waveguides, antennas, and other components that work up there. The situation is much like radar during WWII; there were a few components that could do specific things at radar frequencies (then 60MHz to 1.2GHz), but general electronics wasn't there yet. Most of the electronics in radars of that period ran at far lower speeds. They still worked.
From the comments, I thought this was youtube...
... or are they going to try to make a CPU/GPU core at this speed?
In the long run, maybe. In the short run you aren't going to like it. A very stereotypical microwave LNA MMIC operating around a factor of 100 lower then this device frequency (in other words, cheap and off the shelf) consisting of a couple transistors is biased much like a LED... couple volts, couple dozen mA. Lets call it 4 volts at .040 amps thats 160 milliwatts per device. For rounding purposes lets say a tenth of a watt per transistor. So if you have a roughly quarter million transistor original 386 a 10 GHz discrete 386 made out of microwave transistors would draw about 30 or so KW. Which is quite a lot of power. Of course you don't need low noise small signal performance or great fan in / fan out ratios... Regardless high speed individual devices certainly like their DC power.
The problem with making processors fast is keeping them fed with something to do. CPU tech always seems to lead memory/IO/algorithm design, I can't remember an era when the "memory guys" were waiting on the "processor guys" to catch up. With current tech a 1 THz CPU would merely spend 99.9% of its time in idle waiting for memory... But nothing in the world could run a NOP or an endless loop faster than that device.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Incorrect. Gain is unitless (Vout/Vin), and decreases pretty much proportionally to the inverse of the frequency on amplifiers, so chip makes use something called the Gain Bandwidth Product (GBP) instead of the 'pure' gain, because it is a much more useful number for specifying actual transistor/amplifier performance in real live working conditions. And the unit of the GBP, is, you guessed it! Hz. Thus, a transistor with a GBP of 0.85THz will have a gain of 1 at 0.85THz, a gain of 2 at 0.425THz etc. When I see a gain with units in Hz I subconsciously think 'GBP' and don't even miss a beat...
See http://en.wikipedia.org/wiki/Gain%E2%80%93bandwidth_product if my explanation doesn't make sense.
Help I am stuck in a signature factory!