Eric, 

Your calculations are correct, but present a problem.
At least to me.
 It is very easy to generate a broad spectrum with a peak of some 30THz.
Just heat up your cooking plate, so to say.
The problem -to my opinion-  is twofold:

a) spatial:
Any emitter has a certain area-density of emission. and the best we can do is 
concentrate this emission onto 
the receiver 1:1, on said area basis. The sun being a good example. 
Surface-temperature of the sun being say 5000K. You never can surpass this 
temperature at the receiving side (via a burning glass or concentrating 
mirror). 

Emitters like the sun or a heating plate are variants of Lambert-emitters.
https://en.wikipedia.org/wiki/Lamberts_cosine_law
To collect all those emissions, you need a big lens, especially if emitter and 
receiver are whithin close distance (unlike the sun)


b) spectral

now, if You want say 30--30.1THz, you cut out only a small segment of the whole 
emission.
The smaller the interval of interest, the smaller the amount of energy within 
that, right?
If You translate this to area-density, You get uW to mW at best per mm2.


Now, to overcome this, you need a generator, like a Laser or some other 
electronic device (RF-generator) with an antenna, which would look quite cute, 
like a wood of nanowires.

Now in the 30THz regime there are no generators, only Lasers. (Electronic 
generators in the 30GHz regime are quite a feat currently. 
And those are extremely low power. See eg LeCroy, the 
oscilloscope-manufacturer. They try to conquer the 100Ghz regime, which 
is 0.1THz, a meager factor of 300 below 30THz. )
THz lasers (say: 5THz) of significant power are a research topic. Google "High 
power THz Laser" and You see what I mean.
The highest I could see is a theoretical power of 100W with efficiency in the 
1%-region.
So this is not an attractive option.

As a final comment:
To bring a nanostrucure into resonance needs, say a certain specific frequency 
with a bandwidth of 1%. This is just a reasonable guess.
All other frequencies present possibly/probably -I do not know- HINDER/PREVENT 
the effect!

The philosopher in me sees this as a feature, not a bug in the construction of 
the Universe.
In the other case it would have exploded long time ago,

So the stability of the universe, as we experience it, is a living proof for 
affairs as they are. A tautology this is.

This is not quite the same as the anthropic principle, but some close relative.

Tricking this is a nifty endeavor.
Guenter


________________________________
 Von: Eric Walker <eric.wal...@gmail.com>
An: vortex-l@eskimo.com 
Gesendet: 4:56 Freitag, 27.Juli 2012
Betreff: Re: [Vo]:FYI: THz pulses can drive lattice vibrations directly...
 

On Thu, Jul 26, 2012 at 4:17 PM, Guenter Wildgruber <gwildgru...@ymail.com> 
wrote:


guys, whatever that is, do You really think that Rossi put something like that 
into real world commercial operation?
>THz pulses with significant energy?
>
From my reading I've concluded that THz is basically infrared.  Sometimes I've 
seen a distinction made between it and infrared, and at other times I have not:

http://en.wikipedia.org/wiki/File:Light_spectrum.svg

An application on a Web page is telling me that the blackbody radiation for an 
object at 300 C (573 K) is 30 THz, with a lower limit of 24 THz and an upper 
limit of 37 THz.  So 300 C would seem to be the goldilocks zone as far as 
terahertz radiation is concerned.  You don't need a fancy terahertz RF pulse 
device; you just heat something up.

Eric

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