THz radiation detection with a conductor

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Mikhail_MR
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Hello!
Is it possible to detect THz radiation (300 GHz - 1 THz) with conductor or dipole antenna used to detect radio waves?

I know that THz radiation may be detected in spectroscopic set-ups with a photoconductive antenna based on the semiconductor. In this case, the light from laser create free electrons and holes and the oscillation of the electric field of the THz radiation leads to the current on the antenna. Can I use only the oscillation of E-field to make current on the antenna if I use the conductor?

Is it correct that the limitation that the size of the antenna must be in order with wavelength is the reason?

With best regards!
Mikhail_MR
 
Mikhail_MR said:
Is it possible to detect THz radiation (300 GHz - 1 THz) with conductor or dipole antenna used to detect radio waves?
Yes, it is possible to use small metallic dipoles, but there are many problems. Far-IR is radiated by black-body objects at room temperatures, including the atmosphere. The atmosphere absorbs Far-IR.
https://en.wikipedia.org/wiki/Atacama_Large_Millimeter_Array

Semiconductor technology has now passed 300GHz = 1mm. Heterodyne down-conversion receivers made from SiGe single chip integrated mixers and oscillators are becoming available. They have application in molecular spectroscopy and fingerprinting chemical materials, also for security and medical imaging. The mass production of Far-IR data links may stimulate the next leap forward in the 300 GHz to 1 THz band.

Mikhail_MR said:
Is it correct that the limitation that the size of the antenna must be in order with wavelength is the reason?
Not really. Semiconductor development has limited the development of Far-IR. The antenna will need to be printed as a phased array of dipoles or have a parabolic reflector to make up for the very small aperture of millimetre wavelength dipoles.