In a groundbreaking advancement poised to transform the landscape of wireless connectivity, researchers have unveiled a novel dual-broadband liquid-crystal programmable metasurface (LCPM) designed specifically for terahertz wireless communications. This state-of-the-art device addresses one of the most pressing challenges in emerging terahertz networks: maintaining reliable communication links in scenarios where direct line-of-sight (LoS) paths are obstructed. Published in the prestigious journal Engineering, this study brings to light a solution that promises not only flexible beam manipulation across two key frequency bands but also stable, high-speed data transmission, all while navigating the complexities of non-line-of-sight environments.
Terahertz communication stands at the forefront of next-generation wireless technologies, offering spectacularly wide bandwidths that can support ultra-high data rates and minimal latency. However, exploiting the terahertz frequency spectrum introduces significant technical hurdles. Terahertz waves inherently suffer from high propagation losses, limited diffraction, and poor penetration capabilities, which together make sustaining signals in cluttered or obstructed environments especially challenging. Conventional reflective surfaces—both passive and active—fall short in adaptability and efficiency at these frequencies. Passive reflectors lack the dynamic programmability to adapt to user mobility, while semiconductor-based intelligent surfaces grapple with prohibitive costs and manufacturing difficulties at terahertz bands.
The innovation detailed by Yuan Fu, Yuanbo Li, and colleagues introduces an elegant alternative—a liquid-crystal-based programmable metasurface that capitalizes on the unique properties of anisotropic meta-atoms. These subwavelength structural units exhibit differential electromagnetic responses depending on the polarization of the incident terahertz waves. This intelligent design enables the LCPM to operate simultaneously in two distinct bands: the W band at 94 GHz under x-polarized incidence and the D band at 140 GHz with y-polarized waves. The metasurface achieves 1-bit phase coding, carefully engineered to maintain a phase difference within approximately 180° ± 20° across broad frequency ranges.
Scaling up the architecture, the full metasurface array encompasses 2,500 meta-atoms, arranged in a 50×50 matrix which is further partitioned into 25×25 super-elements. Each super-element is independently addressable, providing a high degree of freedom in beamforming and steering capabilities. Through sophisticated partition coding schemes, the LCPM system can dynamically switch between dual-beam steering, single-beam scanning, and dual-band independent control. This flexibility manifests in real-time adaptability to changing user positions and environmental conditions, a critical advantage over passive reflectors.
Crucially, this research goes beyond theoretical design and simulation. The authors constructed an experimental terahertz wireless communication platform to rigorously verify the practical performance of the LCPM device. In realistic scenarios where LoS paths were deliberately obstructed, the metasurface dynamically reconfigured the communication channel by adjusting coding patterns. This approach successfully restored stable connections that fixed passive surfaces could not maintain, proving the metasurface’s merit in overcoming line-of-sight limitations inherent to terahertz links.
The system’s versatility extends to supporting advanced digital modulation formats, including quadrature phase-shift keying (QPSK), 16-quadrature amplitude modulation (16-QAM), and 64-QAM, seamlessly across both operational frequency bands. Demonstrating remarkable robustness, the platform supported real-time transmission of high-definition video content without performance degradation. Additionally, broadband functionality was confirmed through operational continuity over a 10-GHz bandwidth within the D band, yielding consistent error vector magnitude metrics across the targeted frequency span.
Long-range transmission experiments further underscored the metasurface’s potent capabilities. The device maintained reliable connectivity over extended distances, a fundamental requirement for future ubiquitous wireless networks that demand coverage beyond immediate proximity. This capability is particularly notable given the pronounced attenuation typical of terahertz waves, marking a significant step forward for flexible and scalable terahertz communication systems.
From a material perspective, the decision to employ liquid crystals as the tuning medium offers multiple advantages. Compared to traditional semiconductor-based tuning elements, liquid crystals provide low power consumption, cost-effectiveness, a wide phase tuning range, and manufacturability compatible with large-scale metasurface arrays. The electro-optical reconfigurability of liquid crystals facilitates rapid and reversible phase shifts, enabling the dynamic beamforming essential for maintaining communication links in fluctuating environments.
Looking ahead, the research team plans to push the technology envelope by enhancing phase coding resolution beyond 1-bit depth, which could provide finer beam control and increased channel capacity. Efforts to reduce the thickness of the liquid-crystal layer aim to accelerate response times, a critical factor for real-time adaptive wireless systems. Additionally, integration of sensing capabilities within the metasurface architecture is envisioned, allowing the metasurface to simultaneously serve as a communication node and environmental sensor, further improving network intelligence and efficiency.
This pioneering work not only charts a path for next-gen terahertz networks but also sets a new benchmark in programmable metasurface technology. By merging advanced materials science with electromagnetic engineering, the dual-broadband LCPM emerges as a transformative platform capable of overcoming traditional barriers posed by terahertz propagation physics. The implications are vast, potentially enabling new applications ranging from high-speed personal communications to advanced sensing and imaging systems integrated within smart environments.
The paper “A Dual-Broadband Liquid-Crystal Programmable Metasurface and Its Application in Terahertz Wireless Communications,” authored by Yuan Fu, Yuanbo Li, Xiaojian Fu, and their team, heralds a promising future where stable, high-capacity wireless networks can function seamlessly even without direct line-of-sight. This innovation paves the way for the widespread adoption of terahertz communication in practical, real-world scenarios.
Subject of Research: Terahertz wireless communication using liquid-crystal programmable metasurfaces to enable dual-broadband beam steering and stable non-line-of-sight links.
Article Title: A Dual-Broadband Liquid-Crystal Programmable Metasurface and Its Application in Terahertz Wireless Communications
News Publication Date: 15-Apr-2026
Web References:
https://doi.org/10.1016/j.eng.2025.08.040
https://www.sciencedirect.com/journal/engineering
Image Credits: Yuan Fu, Yuanbo Li et al.
Keywords
Terahertz communication, programmable metasurface, liquid crystal, dual-broadband operation, non-line-of-sight wireless, beam steering, phase coding, W band, D band, modulation schemes, electromagnetic wave control, intelligent reconfigurable surfaces
