Welcome to the official website of the Terahertz Research Group.

What We Do

We study the efficient generation and detection of THz radiation, as well as how THz waves interact with matters.

In this lab, we play with, including but not limited to, the following scientific jargons:

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What is “Terahertz”?

The etymology of this word comes from Greek, so do most of the units’ prefixes, for which “tera(τέρας)” translates to “monster”. Considering its magnitude, 1 THz = 1 × 1012 Hz, whoever came up with the name didn’t use the wrong Greek vocabulary. As the name suggests, terahertz waves refer to the electromagnetic radiation that oscillates around 1×1012 times per second.

Electromagnetic frequency spectrum.

The THz radiation interval is roughly defined to be within 0.1 – 10 THz (0.03 – 3 mm) by the International Telecommunication Union, whereas other definitions also exist depending on different fields of scientific interests. Since the practice of THz research is varied among different scientists in optics, physics, chemistry, and engineering, it is important to address some commonly accepted parameters that are equivalent to 1 THz:

Value Equation
Frequency1 × 1012 Hzν
Angular Frequency6.28×1012 rad/s2πν
Period1 ps1/ν
Photon Energy4.14 meV
Wave Number33.3 cm-11/λ
Temperature48 Khν/kB

Did You Know?

The first-ever image of a Black Hole captured by the Event Horizon Telescope (EHT) was actually captured in the THz radiation regime.

The Eye of Sauron M87 supermassive black hole. Credit: EHT Collaboration

The EHT made this observation at a wavelength of 1.3 mm, which is equivalent to 0.23 THz.

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