does anyone want to discuss Terahertz wave?
THz wave application is a relatively new topic between microwave and optics, since you can say that THz is a far-infrared lightwave or a very high freqency microwave.
There are many applications about THz, I'm a graduate student studying this topic now.
This is a great site. Maybe I can find someone interested in this topic.
If anyone have interest. I can give some infomation about it.
It seems like your topic is quite interesting!
I think you should try to tell many more about Terahertz wave! How do they works and for what applications! What is the problem to implement this technology today?
8O
There are so many methods for generating THz wave!
We can divide them into two group.
One is electronic method,including Gunn Diodes, FET,HBT,RTD(Resonant Tunnelling Diode),etc..
The point of these methods is "transit time" of devices.
But the limitation of these methods about ~0.7THz (or even lower)
The other is optical method, including quantum cascade laser, EO(electro-optics) sampling,Photoconductive antenna,etc..
The point of these method is "transition".
Usually we can get frequency more than 1THz.(much lower than 1THz is very hard for optical method.)
The limitation of these methods is conversion efficiency.
One limitation of THz propagation is absorption of atmosphere. so it's not good yet for communication.
But,
Since there are so many absorption peak of different materials.in THz regime, we can use it to recognize specific material.
THz wave is used to sensing and imaging.
You can see the following website.
http://www.teraview.co.uk/ab_imageLibrary.asp
May this helpful for you guys! :P
The most important part of the optical method in your description is the femto-
second laser.
There were some experiments done where they build a special mixer and mixed to lasers at different frequenies to produce the difference in terahertz range.
Added after 5 minutes:
it's called photomixing
check this out:
http://physics.nist.gov/Divisions/Di...thz/cwthz.html