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Passive Optical Diode Created At Purdue University
wbr1 writes "Researchers at Purdue University have managed to create a silicon device that acts as a passive diode for infrared optical signals. From the Purdue news release: 'The diode is capable of "nonreciprocal transmission," meaning it transmits signals in only one direction, making it capable of information processing, said Minghao Qi (pronounced Chee), an associate professor of electrical and computer engineering at Purdue University. "This one-way transmission is the most fundamental part of a logic circuit, so our diodes open the door to optical information processing," said Qi.' One of the same researchers had already (using similar technology) created a way to convert laser pulses to RF."
Both the summary and TFA are devoid of anything concrete on how this is actually done. It basically says what the title does, they created a diode. Telling me that light entering the opposite side doesn't make it through really doesn't tell me anything the word "diode" in the title doesn't. I'm sure the science behind this particular device is both clever and interesting but you'd never be able to tell since that information is completely missing. Reporting on stories is nice, but shouldn't journalists actually strive to make their articles contain actual information on what they are covering? You'd think a story about a new discovery would actually contain information about how it actually works (since that's the actual "new" part anyway).
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Third Magic @ Blogspot
Why do so many researchers lie so shamelessly to the press? This may be a step in that direction, but it is a rather small one. Key components are missing and a lot depends on the actual characteristics of this device.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
Every time I read about an R&D achievement at an American university, the lead (and often associate) researchers are Chinese nationals.
Do Americans no longer conduct advanced R&D at American universities?
Seems foolishly short-sighted, if so.
Nothing like a Qi spell to give technology a boost...
And maybe he is an American, or is working on his citizenship. This country used to take pride in being a melting pot.
Sheesh, evil *and* a jerk. -- Jade
The "most fundamental part" of logic isn't one-way transmission, it's the ability to control that transmission by applying a voltage to the transistor's gate. The fact that current will only flow one direction between the emitter and the collector is really not that important by comparison.
You can't build logic from diodes.
http://simple.wikipedia.org/wiki/Diode
http://simple.wikipedia.org/wiki/Logic_gate
All those degrees in looking things up online finally paid off. You're welcome, citizen!
A transistor acts as an electrical switch. Basically, it means that when an input is provided, the rest of the circuit can do something, but at the same time the input is electrically isolated from the rest of the circuit.
Before transistors, there were relays and tubes which accomplished the same thing. They were slower, larger, hotter, and used a lot more electricity. And they were prone to burning out. As a result, computers were hopelessly complicated, the size of small rooms, and were programmed with a screwdriver. And "bugs" in the computer program were sometimes, literally, bugs. A moth, in at least one story. And an IBM chairman famously stated that he saw a world-wide market for about 5 computers.
Then the digital transistor came along and revolutionized that. They were smaller, faster, and required much less power. And they were cheaper, too. The integrated circuit - millions of transistors etched onto a single silicon die - revolutionized that further.
A transistor also acts like a diode, in that it only lets current flow in one direction. But note that this isn't really even necessary: relays, for instance, didn't prevent current from flowing backward. The main thing is that the input is electrically isolated from the output, not that it allows current to flow in only one direction.
So basically, they have everything required to build an optical transistor, except for the switching part. Which is kind of the more important part anyway.
Seeing as the positive aspects (applications, reasons why this is a good thing, even the basics of the theory of photonics) are included in the first five sentences of TFA (which I will refrain from pasting here, out of respect), I'm not sure how my post could be assigned even that bare step above. If you are looking for a laypersons description of the optics theory behind the device design, I can assure you by it's very nature, such an explanation does not exist. If you are looking for a more metaphysical explanation of why faster computers are a truly POSITIVE thing (computer's degrade social fabric, you know) then I'm afraid I can't help you, but can tell you this is probably not the right venue to look for those answers.
We're on the threshold of a lot of things, for a long time, before they become reality.
Newton wasn't a lone genius (parallel development notwithstanding) he was just the right man at the right time, standing on the shoulders of the right giants.
I suspect, once ITER is complete, or maybe it's successor, and practical fusion power becomes reality, then we'll just as equally forget that "we were on the threshold" for over 50 years.