Terahertz (THz) Waves: Advantages and Disadvantages

This page explores the advantages and disadvantages of Terahertz (THz) waves, outlining their benefits and drawbacks.

What is Terahertz (THz)?

Introduction: “Tera” signifies 10¹². Terahertz refers to the region in the electromagnetic spectrum spanning from 0.3 to 10 terahertz frequencies. This radiation resides between microwave and infrared radiation.

Essentially, it’s an extension of microwave and millimeter-wave frequency bands, promising greater communication bandwidth. Terahertz frequencies exhibit characteristics of both microwave and infrared (IR) radiation.

Like IR and microwave waves, THz waves travel in a Line-of-Sight (LOS) manner and are non-ionizing. Furthermore, akin to microwaves, THz waves can penetrate various non-conducting materials like clothes, wood, paper, plastic, cardboard, and ceramics. However, metals highly reflect terahertz radiation.

THz wavelengths range from 1 mm to 0.1 mm. Because THz radiation starts at a wavelength of 1 mm and goes below it, it is known as the submillimeter band. This frequency band goes by various names such as T-rays, T-waves, T-lux, and T-light.

Terahertz frequencies are useful in spectroscopy, pulsed imaging, impulse ranging, communication, sensing, security, mine detection, and bio-chemical agent detection. Ongoing research into viable THz radiation sources, detectors, and modulators is boosting the potential of using Terahertz in wireless communications.

Benefits or Advantages of Terahertz (THz)

Here’s a look at the upsides of Terahertz technology:

• High Bandwidth: Terahertz offers significantly greater bandwidth compared to microwave frequencies, exceeding the capabilities of wireless protocols like 802.11b.
• Penetration of Non-Conducting Materials: THz radiation can readily pass through many non-conducting materials.
• Imaging and Networking Applications: Suitable for image sensing and high-bandwidth wireless networking systems over short distances (approximately 10 to 100 meters).
• Safety: It poses minimal risk to the human body due to its non-ionizing nature.

Drawbacks or Disadvantages of Terahertz (THz)

And now, the downsides:

• Limited Range: Not suitable for long-range communication due to scattering and absorption by elements like clouds, dust, and rain.
• Limited Penetration: Offers less penetration depth than microwave radiation and has difficulty penetrating clouds and fog. It cannot penetrate liquid water or metal.
• Detection Challenges: Detecting terahertz frequencies is difficult because black body radiation at room temperature is very strong at these frequencies.
• Cost and Availability: Sources, detectors, and modulators are not readily available at affordable prices, hindering its widespread commercial adoption in communication systems.

Conclusion

The characteristics of THz radiation – its reflectivity by metals and high absorption by water – present both advantages and disadvantages depending on the specific application.