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In terahertz (THz) photodetection, the efficient interaction between light and matter is crucial for enhancing material properties in nonequilibrium states. This work introduces an innovative approach using spiral plasmonic architectures to effectively control inversion‐symmetry coupling, promoting the operational efficiency of light‐induced hot‐carrier effects in the THz band. The strategic design of the spiral structures, focusing on chirality and symmetry, enables the successful manipulation of a self‐driven photocurrent, adapting its direction and magnitude as needed. This design facilitates the improvement of THz detectors in terms of sensitivity and responsiveness. Additionally, the integration of asymmetric metallization and black phosphorus in the detectors has achieved noteworthy performance metrics, such as a maximum responsivity of 70.2 V W−1 at 0.30 THz, a fast response time below 6 µs, and a noise‐equivalent power lower than 1.95 × 10−10 W Hz−1/2. Harnessing the potential of light‐induced hot carrier effects and advanced band‐structure engineering, this research offers a pragmatic approach for the development of high‐efficiency THz photodetectors, opening new avenues for applications like remote sensing and rapid imaging. [ABSTRACT FROM AUTHOR]

The emergence of novel topological semimetal materials, accompanied by exotic non‐equilibrium properties, not only provides a fertile playground for a fundamental level of interest but also opens exciting opportunities for inventing new applications by making use of different light‐induced effects such as nonlinear optics, optoelectronics, especially for the highly pursued terahertz (THz) technology due to the gapless electronic structures. Exploring type‐II Weyl semimetal endowed with the richness of quantum wavefunction and peculiar band structure, underlie strong nonlinear coupling with THz waves. Here, the selective growth of type‐II Weyl semimetal NbIrTe4 by means of a self‐flux approach is reported, which hosts strongly tilted Weyl cones and exotic Fermi arcs. The oscillating THz field induced by the antenna is engineered in terms of planar metal‐topological semimetal‐metal structure, along with van der Waals stacking, which allows for self‐powered photodetection at room temperature. The results elucidate the superior performance of NbIrTe4‐graphene heterostructure‐based photodetectors with responsivity up to 264.6 V W−1 at 0.30 THz, fast response of 1 µs as well as low noise equivalent power ˂0.28 nW Hz−0.5 is achieved, already exhibiting high‐quality imaging at THz frequency. The results promise superb impacts in exploring topological Weyl semimetals for efficient low‐energy photon harvesting. [ABSTRACT FROM AUTHOR]

Owning unique optical and electronic properties, two dimensional (2D) materials have made remarkable strides in the field of photodetection applications. However, achieving highly sensitive and ultra‐broadband detection from microwave to terahertz (THz) range (0.02–0.54 THz) remains a significant challenge for photodetectors. This study presents a self‐powered THz photodetector based on VSe2 and its van der Waals heterostructure. The photoresponse of the photodetector is primarily attributed to the photothermoelectric effect. At room temperature, the device exhibits lower noise equivalent power values of 21 pW Hz−1/2 at 0.28 THz. This work has achieved ultra‐broadband detection and demonstrated the potential for large‐area imaging, providing a new avenue for the application of THz technology in nondestructive testing and biometric identification fields. [ABSTRACT FROM AUTHOR]