Article
Optics
Muhammad Talal Ali Khan, Haisu Li, Yajing Liu, Gang-Ding Peng, Shaghik Atakaramians
Summary: This article experimentally demonstrates a compact terahertz dispersion compensator based on subwavelength gratings. The low-loss cyclic olefin copolymer is utilized for fabricating the gratings, which exhibit high negative group velocity dispersion and birefringence for achieving dispersion compensation in terahertz communication systems.
Article
Optics
Hichem Guerboukha, Yasith Amarasinghe, Rabi Shrestha, Angela Pizzuto, Daniel M. Mittleman
Summary: This paper introduces the application of hot stamping technology for rapid prototyping of terahertz devices, including metasurfaces and wire-grid polarizers, demonstrating the versatility and cost-effectiveness of the technique.
Article
Physics, Applied
Yuanyuan Bai, Chunmei Ouyang, Zhibo Yao, Shilei Liu, Yanfeng Li, Liyuan Liu, Jianqiang Gu, Jiaguang Han, Weili Zhang
Summary: In this work, a metasurface with a multi-angle polarization conversion function is proposed, which consists of a top metal structure layer, a dielectric spacer, and a bottom metal film. The unit cell in the metal structure layer consists of two L-shaped elements which are symmetric about the -45 degrees axis and rotated clockwise and counterclockwise around the center, respectively. Compared with recent reports, the structure proposed here is more flexible in polarization conversion and more suitable for practical applications and has great potential in the terahertz field.
APPLIED PHYSICS LETTERS
(2023)
Article
Optics
Yu-Han Chang, Vanna Chrismas Silalahi, Yun-Ting Yang, Yu-shiang Wen, Watson Kuo
Summary: The study presents a systematic investigation of resonator coupling between split-ring resonators (SRRs) and complementary split ring resonators (CSRRs) for any orientation combination. The method estimates the coupling strength through a linear combination of periodic functions based on two orientation angles, with a sinusoidal expansion of up to the 3rd order. This approach provides a satisfactory explanation of the band structure of SRR chains using a microwave-hopping model, facilitating the exploration of exotic photonic band structures based on tight-binding theory.
Article
Materials Science, Multidisciplinary
Joao C. Serra, Mario G. Silveirinha
Summary: We introduce a homogenization approach to characterize the dynamical response of a generic dispersive space-time crystal in the long-wavelength limit. The theory is applied to dispersive space-time platforms with a traveling-wave modulation, and it is shown that for long wavelengths the effective response may be described by a frequency-dependent permittivity. The article discusses the peculiar physics exhibited by dispersive space-time crystals, such as anomalous permittivity dispersion, alternate gain and loss regimes, and multiple resonances in the quasistatic regime.
Article
Materials Science, Multidisciplinary
Jiaying Wang, Florian Allein, Cecile Floer, Nicholas Boechler, James Friend, Oscar Vazquez-Mena
Summary: This study presents a novel technology to fabricate acoustic metamaterials in water using microstructured silicon chips, enabling their operation in the MHz range for applications in biomedical ultrasound. The metamaterials are formed by assembling silicon chip unit cells that incorporate silicon nitride membranes and Helmholtz resonators. Finite-element method simulations and experimental measurements confirm the negative-index behavior of the material in the 0.25-0.35 MHz range. This work opens up new possibilities for achieving relevant frequencies for biomedical ultrasound applications using silicon technology microfabrication.
ADVANCED MATERIALS TECHNOLOGIES
(2022)
Article
Mechanics
Yao Huang, Jiu Hui Wu, Yunzhong Lei, Jiamin Niu
Summary: In this study, meta-honeycombs were designed by adding local resonance plates (LRP) to improve impact resistance. The negative mass and directional bandgap properties of the LRP were investigated to predict the impact resistance of the meta-honeycombs. Experimental and simulation results verified the effectiveness of three meta-honeycombs with different core structures in protecting against impact and blast waves. The mechanical properties of the meta-honeycombs were further optimized by coupling different resonators in the LRP.
COMPOSITE STRUCTURES
(2023)
Article
Physics, Multidisciplinary
Hailin Ren, Shijun Ji, Ji Zhao, Handa Dai
Summary: A plasmon-induced terahertz metamaterial absorber is introduced, using a gold bottom layer to block the transmission of terahertz waves, with a topas layer separating the pattern layer and ground layer. The absorber exhibits a 90% absorption bandwidth frequency range of 4.6-7.7 THz, with an average absorption rate of 97.6% in this range. It has polarization insensitivity due to its geometric symmetry, and can maintain over 80% absorption even at an incidence angle of 60 degrees. The absorber also shows good linear frequency shift with refractive index change, with a sensitivity of 1100 GHz per refractive index unit (GHz/RIU), making it suitable for complex electromagnetic scenarios or as a sensing element.
Article
Engineering, Electrical & Electronic
Tomoyuki Sasaki, Matni Harada, Moritsugu Sakainoto, Kohei Noda, Keiichi Itoh, Hiroyuki Okamoto, Hiroshi Ono
Summary: We report a metasurface for polarization converters in the terahertz spectral range. The metasurface consists of a metal mesh with isotropic apertures and a uniaxially anisotropic dielectric medium. It exhibits a large birefringence and transmissive retardation, making it useful for transmissive polarization conversion in the THz range.
IEEE PHOTONICS JOURNAL
(2022)
Article
Engineering, Electrical & Electronic
Weijian Cai, Jianfang Zhu, Youpeng Yang, Xiaoran Wang, Zhengfang Qian, Shuting Fan
Summary: In this study, a double-open hexagonal ring metamaterial (MM) with high refractive index sensitivity was designed and fabricated to improve the detection sensitivity of terahertz (THz) biosensors. The resonant properties of the MMs were demonstrated through simulations and experiments. The MM sensor showed high sensitivity and low detection limits to glucose and bovine serum protein (BSA) solutions, indicating potential applications in the THz biomedical field.
IEEE SENSORS JOURNAL
(2023)
Article
Engineering, Electrical & Electronic
Haizi Yao, Hongying Mei, Weiwei Zhang, Shuncong Zhong, Xiangfeng Wang
Summary: This study proposes a terahertz metamaterial refractive index/thickness sensor with low-frequency Fano resonance and high-frequency electromagnetically induced transparent (EIT) resonance. The simulated and experimental results demonstrate that the sensor has high sensitivity in refractive index and thickness sensing, making it suitable for biological and chemical sensing applications.
IEEE PHOTONICS JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Jitong Zhong, Xiaocan Xu, Yu-Sheng Lin
Summary: The MEMS-based tunable terahertz metamaterial (TTM) exhibits tunable characteristics in resonance, polarization-dependent, and electromagnetically induced transparency (EIT) due to the configuration of eSRR. It shows potential application in refraction index sensors with good sensing performances.
Article
Engineering, Electrical & Electronic
Ayesha Mohanty, Om Prakash Acharya, Bhargav Appasani, S. K. Mohapatra, Mohammad S. Khan
Summary: This paper presents and evaluates a new terahertz metamaterial absorber (MMA) for sensing applications, which offers high sensitivity and good detection performance for changes in refractive index of the environment.
IEEE SENSORS JOURNAL
(2021)
Review
Nanoscience & Nanotechnology
Riccardo Degl'Innocenti, Hungyen Lin, Miguel Navarro-Cia
Summary: The terahertz range is a fast-evolving field with unique applications in spectroscopy, quantum electronics, sensing, and wireless communications beyond 5G. Among various approaches, metamaterial-based terahertz modulators have shown great success due to their ease of realization, high efficiency, and spectral versatility. This review presents the latest developments in this field, with a focus on key applications in sensing, wireless communications, and quantum electronics that have benefited from these advancements.
Article
Optics
Jing Zhao, Chunmei Ouyang, Xieyu Chen, Yanfeng Li, Caihong Zhang, Longcheng Feng, Biaobing Jin, Jiajun Ma, Yi Liu, Shoujun Zhang, Quan Xu, Jiaguang Han, Weili Zhang
Summary: Dynamic control of metasurfaces for adjustable electromagnetic properties has been studied in a terahertz polarization converter, allowing for a high polarization conversion ratio across a broad frequency range. This scheme has potential applications in integrated terahertz systems, sensing, imaging, and communications.
