Article
Engineering, Electrical & Electronic
Pengfei Cao, Yuan Li, Yuyao Wu, Zhengnan Yuan, Shenglin Li, Lin Cheng
Summary: A graphene-based planar terahertz EIT-like metamaterial was proposed, with transparent window controlled by carrier mobility. The sensitivity reached 1.6 THz/RIU in optimal conditions, showing potential for refractive index detection applications. The design offers a practical method for the development of optical switches, biochemical molecular detection, and slow light equipment.
IEEE SENSORS JOURNAL
(2021)
Article
Engineering, Electrical & Electronic
Aruna Veeraselvam, Gulam Nabi Alsath Mohammed, Kirubaveni Savarimuthu
Summary: This study presents a highly sensitive THz sensor for detecting biological samples, with a small footprint and high sensitivity. The sensor's sensitivity was estimated using absorption characteristics, and it was evaluated for various materials and biomedical samples, showing an average sensitivity of 1936 GHz/RIU.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
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
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
Chemistry, Multidisciplinary
Subin Jo, Min-Gyu Bae, Joong-Wook Lee
Summary: The study found that meta-rotamers composed of meta-molecules based on the difference in the spatial position of their component meta-atoms can achieve tunable Fano-like resonance through rotations, providing potential pathways for exploring novel THz devices and developing high-level functionalities in metamaterial-based devices.
APPLIED SCIENCES-BASEL
(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
Chemistry, Multidisciplinary
Peng Wang, Rui Hu, Xiaotian Huang, Teng Wang, Shulin Hu, Min Hu, Huanhuan Xu, Xiaoyu Li, Keshuai Liu, Shengxiang Wang, Lei Kang, Douglas H. Werner
Summary: This paper demonstrates a chiral metamaterial capable of exhibiting strong chiroptical responses at THz frequencies using a two-step textile manufacturing approach, which is of great significance for the control of THz radiation.
ADVANCED MATERIALS
(2022)
Article
Multidisciplinary Sciences
Daquan Yang, Weiguang Wang, Erpeng Lv, Haiming Wang, Bingchao Liu, Yanzhao Hou, Jin-Hui Chen
Summary: A programmable vanadium dioxide metasurface is proposed for THz frequencies, which can switch between insulating and metallic states via external electrical stimulation, allowing for dynamic modulation of the electromagnetic response. By controlling the voltages of different columns, phase gradients are achieved for THz beam steering. Different coding methods offer varying degrees of optical phase control and improved diffraction efficiency.
Article
Engineering, Electrical & Electronic
Zhixia Xu, Yi Wang, Shaojun Fang
Summary: Electromagnetically induced transparency (EIT) is a widely reported destructive interference phenomenon in quantum and classical wave systems, showing sharp transmission windows within stop bands. A planar microwave circuit based on EIT-like spectrum is designed for dielectric characterization of liquid mixtures, with the complex permittivity affecting the transmission window's center frequency and quality factor. The design allows for high sensitivity measurement of solid samples with low permittivity dynamic range and can be easily fabricated for testing various materials.
IEEE SENSORS JOURNAL
(2021)
Article
Chemistry, Physical
Alin Gheorghita Mazare, Yadgar Abdulkarim, Ayoub Sabir Karim, Mehmet Bakir, Mohamed Taouzari, Fahmi F. Muhammadsharif, Bhargav Appasani, Olcay Altintas, Muharrem Karaaslan, Nicu Bizon
Summary: In this study, a triple band perfect metamaterial absorber based on Pythagorean fractal geometry was proposed and analyzed for terahertz sensing applications. The design exhibited enhanced sensing performance and achieved three intensive absorption peaks within the desired frequency range. The proposed design was found to be sensitive to changes in substrate type, resonator material, substrate thickness, and refractive index of the surrounding medium. The metamaterial sensor demonstrated high sensitivity to variations in thickness at a fixed analyte refractive index, making it suitable for biomedical applications.
Article
Nanoscience & Nanotechnology
Pengfei Cao, Yuan Li, Yubo Deng, Yuyao Wu
Summary: A terahertz constant frequency reconfigurable metasurface based on tunable electromagnetically induced transparency (EIT)-like property was designed, showing evident transparency window at 1.98 THz with over 80% amplitude. By individually reconfiguring the Fermi energy of each resonator, the EIT-like effects, transparency window amplitude, modulation speed and group delay could be actively controlled.
Article
Optics
Yonggang Zhang, Fu Qiu, Lanju Liang, Haiyun Yao, Xin Yan, Wenjia Liu, Chengcheng Huang, Jianquan Yao
Summary: This letter presents a fabricated Dirac point modulator of a graphene-based terahertz electromagnetically induced transparency (EIT)-like metasurface. The modulation is achieved through three stimulus modes: optical pump, bias voltage, and optical pump-bias voltage combination. The position of the Dirac point can be evaluated approximately by analyzing the transmission spectrum fluctuation. The findings demonstrate a method for designing ultrasensitive terahertz modulation devices.
Article
Engineering, Electrical & Electronic
Mingming Chen, Zhongyin Xiao, Fei Lv, Zhentao Cui, Qidi Xu
Summary: A simple and multi-layer metamaterial made of graphene is proposed to achieve excellent manipulation of the EIT-like effect. By adjusting the Fermi level of graphene, tunable EIT-like effect can be obtained. In addition, wideband EIT-like effect with high transmission can be achieved by adjusting the geometrical parameters of the metamaterial.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2022)
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.
Article
Chemistry, Analytical
Yeeun Roh, Sang-Hun Lee, Jisung Kwak, Hyun Seok Song, Seulgi Shin, Yun Kyung Kim, Jeong Weon Wu, Byeong-Kwon Ju, Boyoung Kang, Minah Seo
Summary: This report introduces a highly improved THz imaging technology by comparing complementary metamaterials based on Babinet's principle, showing significant potential applications in producing clear contrast images in biological samples.
SENSORS AND ACTUATORS B-CHEMICAL
(2022)
Article
Optics
Shoujun Zhang, Xieyu Chen, Kuan Liu, Haiyang Li, Yuehong Xu, Xiaohan Jiang, Yihan Xu, Qingwei Wang, Tun Cao, Zhen Tian
Summary: This article introduces a nonvolatile, reconfigurable, and dynamic Janus metasurface using phase-change material Ge2Se2Te5 (GST) in the terahertz (THz) regime. The reversible switching characteristic of GST on large areas is demonstrated, and a multiplex metasurface scheme is proposed. Various applications such as dynamic beam splitter, bifocal metalens, and switchable metalens/focusing optical vortex generators are designed and experimentally characterized. The development of multifunctional and compact THz devices can be facilitated by this scheme.
PHOTONICS RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Yuehong Xu, Quan Xu, Xueqian Zhang, Xi Feng, Yongchang Lu, Xixiang Zhang, Ming Kang, Jiaguang Han, Weili Zhang
Summary: This study proposes a new design scheme using all-metal stereo U-shaped meta-atoms for efficient and broadband manipulation of terahertz polarization. The design is experimentally verified to demonstrate superior performance in polarization control and enriches the design freedom of polarization-related metasurfaces.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Xi Feng, Xieyu Chen, Yongchang Lu, Qingwei Wang, Li Niu, Quan Xu, Xueqian Zhang, Jiaguang Han, Weili Zhang
Summary: This paper proposes and experimentally demonstrates a new method for directly emitting focused THz vortex beams with desired orbital angular momentums. The method utilizes patterned ITO film to generate nonlinear THz emission, achieving effective integration of THz emission and vortex-beam generation.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Optics
Xiaolin Zhuang, Wei Zhang, Kemeng Wang, Yangfan Gu, Youwen An, Xueqian Zhang, Jianqiang Gu, Dan Luo, Jiaguang Han, Weili Zhang
Summary: A C-shape-split-ring-based phase discontinuity metasurface with a liquid crystal elastomer substrate is introduced for infrared modulation of terahertz wavefront. By manipulating the deflection of the substrate, controllable and broadband wavefront steering is achieved, with a maximum output angle change of 22 degrees at 0.68 THz. The liquid crystal elastomer metasurface also demonstrates the performance of a beam steerer, frequency modulator, and tunable beam splitter, which are highly desired in terahertz wireless communication and imaging systems.
LIGHT-SCIENCE & APPLICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Qingwei Wang, Xueqian Zhang, Quan Xu, Xi Feng, Yongchang Lu, Li Niu, Xieyu Chen, Eric Plum, Jianqiang Gu, Quanlong Yang, Ming Fang, Zhixiang Huang, Shuang Zhang, Jiaguang Han, Weili Zhang
Summary: Coupling between different meta-atoms within the unit-cell can be used to control nonlinear THz generation, where achiral coupling provides control over THz field amplitude and chiral coupling makes THz generation sensitive to pump polarization. Multiplexed pump-handedness-selective nonlinear metasurfaces can be realized, allowing for the generation of THz beams with different orbital angular momentum. This approach enables the development of various integrated nonlinear THz devices.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
Guanxuan Guo, Xueqian Zhang, Li Niu, Tong Wu, Xieyu Chen, Quan Xu, Jiaguang Han, Weili Zhang
Summary: We propose a programmable graphene metasurface based on the quantum effect analogue, electromagnetically induced transparency, which enables continuous amplitude and phase tuning of cross-polarized transmission in the terahertz (THz) regime. This programmable scheme allows flexible control over the diffraction angles and focal lengths of the transmitted THz beams, providing new inspirations for THz programmable metasurface devices.
Article
Optics
Xiaohan Jiang, Quan Xu, Yuanhao Lang, Wanying Liu, Xieyu Chen, Yuehong Xu, Hang Ren, Xibin Wang, Su Xu, Xueqian Zhang, Chunmei Ouyang, Zhen Tian, Jianqiang Gu, Jiaguang Han, Weili Zhang
Summary: Geometric phase metasurfaces, a branch of meta-optics, have gained significant attention in recent years. The concept has been extended to near-field regime for the control of surface plasmons (SPs) by rotating dipole sources. However, there are still puzzles and shortcomings, such as the explanation for the reported geometric phases equal to the rotation angle and twice the rotation angle of the dipole sources for SP controls, and the limited control strategies for a single wavelength. In this study, a rigorous derivation of SP excitation by circularly polarized illumination is performed, clarifying the rotation dependence and coordinate correlation of geometric phase control of SPs. Furthermore, a holographic approach is proposed to implement multiplexed geometric phase control, demonstrating the ability to couple and steer incident circular polarizations of different wavelengths and spin directions to specific SP focusing beams. This work paves the way for integrated and multiplexed SP devices.
LASER & PHOTONICS REVIEWS
(2023)
Article
Materials Science, Multidisciplinary
Meng Lian, Ying Su, Kuan Liu, Shoujun Zhang, Xieyu Chen, Haonan Ren, Yihan Xu, Jiajia Chen, Zhen Tian, Tun Cao
Summary: Researchers have achieved switchable and wearable reflection linear polarization conversion in the THz frequency band. By changing the structural state of the material, the converter can continuously adjust the polarization conversion ratio. This switchable converter provides new possibilities for dynamically controlling THz polarization states and has wide applications in THz imaging, spectroscopy, and communications.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Optics
Xieyu Chen, Shoujun Zhang, Kuan Liu, Yuehong Xu, Xiaohan Jiang, Haiyang LI, Xi Feng, Qingwei Wang, Yongchang Lu, Kemeng Wang, Tun Cao, Zhen Tian
Summary: In this paper, a lithography-free approach is proposed to create reconfigurable and nonvolatile THz components using the phase change material Ge2Sb2Te5. THz gratings and ultrathin THz flat lenses are designed and fabricated on ultrathin Ge2Sb2Te5 films to demonstrate the capability of the proposed method. Moreover, more complex THz devices can also be created using this method. This method provides a promising solution for realizing reconfigurable and nonvolatile THz elements.
PHOTONICS RESEARCH
(2023)
Article
Engineering, Electrical & Electronic
Ming Fang, Jian Feng, Guoda Xie, Yongchang Lu, Xueqian Zhang, Jiaguang Han, Zhixiang Huang
Summary: In this work, a nondepleted time-domain model derived from the Maxwell-hydrodynamic model is proposed for simulating the generation of terahertz waves from metallic nonlinear metasurfaces. The proposed model is validated and benchmarked with previous studies and experimental results.
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
(2023)
Article
Optics
Shuangqi Zhu, Bowen Dong, Guanxuan Guo, Xueguang Lu, Quan Xu, Jiaguang Han, Wanxia Huang, Hua Ma, Yongtian Wang, Xueqian Zhang, Lingling Huang
Summary: This paper proposes a dynamic THz metasurface combined with the phase-change material VO2 that can be thermally controlled for optical encryption. By arranging antennas in advance and utilizing the electromagnetically induced transparency effect, a secret image can be encoded into the metasurface. When the temperature exceeds the phase-change temperature, the encrypted hologram can be reconstructed. With the distinct characteristics of VO2, the phase-change temperature required for decryption is not very high, and the entire process is reversible. It is expected that such metasurfaces can be practically applied to the next generation of optical encryption or optical anticounterfeiting in the future with updated processing technology.
LASER & PHOTONICS REVIEWS
(2023)
