
The Truth About Terahertz (2012) - Cieplak
https://spectrum.ieee.org/aerospace/military/the-truth-about-terahertz
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madengr
Though it’s non-ionizing, there is a paper out there about DNA resonance at
mmW and THz. So I suppose you can still get cellular damage.

So a single photon is not ionizing, but I can certainly generate plasmas with
lots of photons at lower energy. So the whole point of ionizing radiation is
that it can induce cellular damage without killing the cell? So this can’t be
done with non-ionizing radiation, even though it can certainly ionize with
average energy?

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marcosdumay
> mmW

Did you mean micro Watt here?

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fulafel
millimeter-waves, like in the high frequency 5G-NR radio - around 50 GHz.

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joss82
Reading this article, it seems that terahertz is only suited for space-based
telecommunication.

Given its super high transfer rate, it would be perfect for a low orbit,
internet-providing satellite constellation. _cough_ starlink _cough_

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baybal2
Attenuation in atmosphere is extreme. But this can be seen as a plus if you
want to limit interference (try wifi in a crowded mall)

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abricot
You don't have to go full terahertz for that. Just look at the difference
between 2.4ghz and 5ghz wifi.

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godelmachine
I had read a research wherein Terahertz was used to read the contents of a
closed book. Wonder how far that research has progressed, or have they tried
to make it applied, ready for some sort of operational results.

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mehrdadn
For reference I think you mean this, right?
[https://news.mit.edu/2016/computational-imaging-method-
reads...](https://news.mit.edu/2016/computational-imaging-method-reads-closed-
books-0909)

~~~
godelmachine
Right you are!

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B1FF_PSUVM
In the comments section:

"""

Terahertz Medicine • a year ago

This review would be different now in 2017.

"""

Any pointers?

~~~
Uberphallus
The laws of physics didn't change, it's great but suffers most of the problems
of IR communication, namely air diffraction/absorption (severely hurting
range) and mostly line of sight communication. Through advanced modulation
schemes one can reach gigabit speeds but it's such an extremely short range[1]
it's no surprise there seems to be no commercial product.

Terahertz signal processing, though, has a much brighter (hah) future ahead,
in medical and security imaging[2].

[1] [http://www.embednet.com/Giga-
IR_General.pdf](http://www.embednet.com/Giga-IR_General.pdf)

[2] [https://codeburst.io/terahertz-thz-gap-tech-for-speedy-
commu...](https://codeburst.io/terahertz-thz-gap-tech-for-speedy-
communication-cb7ccd7ee6fb?gi=bbb3dfdc39d)

~~~
jacquesm
What about interconnects inside a computer?

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tokai2
I’m just speculating. Theoretically if you have vacuum sealed CPU, it could
work. This brings other problems. How would you remove heat released by the
chips in vacuum if there is no airflow.

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jacquesm
That does not make sense.

The distances are so short that you would not have much attenuation from air
at normal pressure / humidity.

Also: (not that it matters), but you can remove heat from chips in vacuum
through IR radiation and through heatpipes connected to the guts of the chips
in the normal fashion (through a heatsink connected to the top of the device).

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brian-armstrong
Don’t we have Terahertz communication already? Fiber optics run on 100 THz
light approximately, no?

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lnx01
From the article: "The terahertz regime is that promising yet vexing slice of
the electromagnetic spectrum that lies between the microwave and the optical,
corresponding to frequencies of about 300 billion hertz to 10 trillion hertz
(or if you prefer, wavelengths of 1 millimeter down to 30 micrometers). "

So, no.

