Re: Nano-Thyristor for AC/DC Conversion


In article <11j4gt9f6t8q8f8@xxxxxxxxxxxxxxxxxx>, manofsan@xxxxxxxxx
says...

> http://physicsweb.org/articles/news/9/9/12/1

> A nano-sized thyristor has been made from a tiny crystal, enabling
> conversion of DC current into AC.

> Would anyone care to comment on the possible applications for this?
> Could this be used to run a nano-sized AC motor, for example?

> Can this serve as an alternative to oscillating piezo-electric crystals
> used in radios or watches?

It's difficult to say what this would be used for except a lab demo
unit, because the article give no salient technical features whatsoever,
except that it runs somewhere in the neighborhood of 40 Hz.

Since I am a professional consumer of high grade crystal (and more
exotic) oscillators, I'll use your wristwatch question as a specific
case. First, in order to be used as an alternative to a crystal in a
wristwatch, these devices would have to be notably better than a crystal
in some way. Note: Not "the same as" but actually "better" because in
the analog world, there is no such thing as a drop in replacement, no
matter what the vendors tell you. Retooling costs are a bitch.

So, how might an oscillator be "better"? Well, it could be cheaper, but
that's unlikely, because the crystal industry is big, established,
mature, and as commoditized as an analog electronics business can be.
Watch-grade crystals are dirt cheap.

It could be more precise or accurate (by any of a dozen different
metrics, none of which I'll bore you with here.) Plausible, but
unlikely... because frankly, watch crystals really don't *need* to be
more accurate than they are now. A few seconds a month is adequate for
everyone. (My gut tells me also that, no, these are not more precise
than crystals, but you can't tell by press release.)

We won't even talk about "smaller" unless someone really needs a
wristwatch that's even smaller than the ones we've got.

Or maybe they could consume less power. Ah, now you're talking... at
least potentially. If your oscillator consumes a significant bit of
your power, and your new nano-oscillator contains much less, then you've
got a potential application in your watch: You can create a watch with
a greatly extended battery life.

These are the criteria by which new technologies must be evaluated,
unless they're offering *truly* new capabilities. The criteria are
often economic in nature. Nanotechnology is no different.

--
John S. Novak, III
The Humblest Man On The Net

.

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