Terahertz Wave Communications and Photonic Technologies

Terahertz (THz) communications occupy the spectral region between microwave and infrared bands, offering unprecedented bandwidth for ultra-high-speed wireless links. The field has advanced through integration of photonic techniques—such as optical heterodyning, photonic-crystal waveguides and on-chip silicon platforms—to generate, modulate and detect signals above 100 GHz. Challenges remain in overcoming free-space path loss, atmospheric absorption and device losses, which have driven innovations in beam control, frequency multiplexing and low-loss interconnects. Engineered surfaces and reconfigurable elements now enable dynamic beam-steering and adaptive link discovery, while frequency-division schemes and compact multiplexers support multi-gigabit-per-second transmission. The confluence of photonic integration and advanced antenna design promises to bridge optical-fibre backbones with wireless access, underpinning next-generation 6G networks and diverse applications in imaging, sensing and security.

Research from Nature Portfolio

Recent studies have demonstrated frequency-division multiplexers capable of error-free dual-channel transmission at aggregate data rates of 50 Gbit s⁻¹, revealing non-uniform angular sensitivity in diffracting THz beams and guiding design of compact demultiplexers. Novel link-discovery protocols employ broadband leaky-wave antennas to perform single-shot alignment of directional beams without phase measurements, enabling rapid node localisation in mobile networks. Electrically reconfigurable THz devices incorporating liquid-metal actuators within waveguides have realised the first active power-splitting switch and channel add–drop filter, preserving high-bit-rate information while dynamically controlling spectral routing.

Terahertz Wave Communications and Photonic Technologies publication trend

The graph below shows the total number of articles in terahertz wave communications and photonic technologies across all publications each year (not limited to Nature Index journals).

Technical terms

Terahertz wave: Electromagnetic radiation in the 0.1–10 THz frequency range, bridging microwave and infrared spectra.

Photonic-crystal waveguide: A dielectric structure with periodic refractive-index modulation that confines and guides light or THz waves.

Reconfigurable intelligent surface: A planar array of controllable elements that can dynamically shape and steer electromagnetic wavefronts.

Leaky-wave antenna: An antenna type that radiates continuously along its length, allowing beam direction to be tuned by frequency.

Frequency-division multiplexing: A method of transmitting multiple data streams simultaneously on distinct frequency channels within the same medium.

References

1. Hardware Aspects of Sub-THz Antennas and Reconfigurable Intelligent Surfaces for 6G Communications. IEEE Journal on Selected Areas in Communications (2023).
2. 1-to-N terahertz integrated switches enabling multi-beam antennas. Optica (2023).
3. Terahertz wireless communications based on photonics technologies.. Optics Express (2013).
4. Single-shot link discovery for terahertz wireless networks. Nature Communications (2020).
5. Electrically reconfigurable terahertz signal processing devices using liquid metal components. Nature Communications (2018).
6. Frequency-division multiplexer and demultiplexer for terahertz wireless links. Nature Communications (2017).
7. Unclad Microphotonics for Terahertz Waveguides and Systems. Journal of Lightwave Technology (2020).