Carbon Nanotubes for Terahertz Waves: Synthesis, Patterning, and Applications

ABSTRACT Terahertz (THz) technology is emerging as a key enabler for high‐speed communications, imaging, and sensing. However, the advancement of THz devices remains hindered by the intrinsic limitations of conventional materials in delivering broadband absorption, efficient emission, and real‐time control of THz waves. Carbon nanotubes (CNTs), with their quasione‐dimensional structure, high carrier mobility, tunable plasmonic response, and pronounced electromagnetic anisotropy, offer a uniquely versatile material platform to address these challenges. This review systematically examines the fundamental properties, controllable synthesis, and precision patterning of CNTs for THz applications. It further surveys the operating mechanisms and recent progress of CNT‐based THz devices, including emitters, antennas, absorbers, detectors, modulators, polarizers, transistors, and amplifiers. Particular emphasis is placed on the roles of photoelectric, thermoacoustic, and plasmonic effects in enabling efficient detection, emission, and dynamic manipulation of THz. Finally, the review discusses emerging opportunities for CNT‐enabled THz technologies, including highly integrated systems, quantum‐effect modulation, and artificial‐intelligence‐assisted design for future applications. This review is organized as follows: Section 1 introduces the advantages of CNTs for THz applications; Section 2 summarizes CNT synthesis and transfer methods; Section 3 highlights representative CNT‐based THz devices for wave generation, modulation, absorption, and processing; and Section 4 presents the conclusions and outlook.