Waveguides are essential in the full deployment of terahertz communication systems. Innovative waveguides are essential to provide versatile signal-processing functionalities. Existing fundamental components typically rely on complex hybridization, making it extremely challenging to go beyond the most elementary functions for constructing future communication systems at THz frequencies.
In a new study, scientists at the Institut national de la recherche Scientifique (INRS) have proposed a novel approach. They developed a new waveguide to overcome those limitations. In combination with diverse waveguide designs, such an approach allows for the realization of a unique platform with remarkable structural simplicity yet featuring unprecedented signal-processing capabilities.
In their study, scientists introduced a novel approach for realizing broadband THz signal processing in metal-wire waveguides by engineering the wire surfaces. They act like pipes for electromagnetic waves and confine their propagation.
Scientists used their concept in the THz regime. It allows for unprecedented flexibility towards manipulating THz pulses propagating within the waveguides. As a result, it will enable more complex signal-processing functionalities like holographic messaging” in 6G.
Junliang Dong, a postdoctoral researcher, said, “We demonstrate that, by engraving judiciously designed grooves with multiscale structures directly on the metal wires, we can change which frequencies are reflected or transmitted (i.e., a THz Bragg grating) without adding any material to the waveguide.”
Scientists have introduced a completely new waveguide geometry: the four-wire waveguide (FWWG). It can sustain two independent waves that are orthogonally polarized, so they do not interfere with each other. It introduced polarization-division multiplexing in THz waveguides, i.e., allowing the two channels of information to be transmitted over a single transmission path.
Professor Roberto Morandotti at the Institut national de la recherche Scientifique (INRS) said, “Our device represents the first THz waveguide architecture, with a new metal-based design, which supports polarization-division multiplexing. In particular, the capability of realizing such complex signal-processing functionality, i.e., the independent manipulation of multiplexed THz signals, has never been achieved elsewhere.”
“This universal approach for the realization of broadband THz signal processing, in combination with novel waveguide designs, paves the way to the next generation network. It will allow for fascinating application scenarios, such as the multi-channel transmission of uncompressed ultra-high-definition video, ultra-high-speed short-distance data transfer between devices, as well as chip-to-chip communications.”
- Versatile metal-wire waveguides for broadband terahertz signal processing and multiplexing. Nat Commun13, 741 (2022). DOI: 10.1038/s41467-022-27993-7