Article
Engineering, Electrical & Electronic
Victor Dmitriev, Nilton R. N. M. Rodrigues, Rodrigo M. S. de Oliveira, Rodrigo R. Paiva
Summary: A rectangular graphene loop antenna for terahertz band was proposed and analyzed in this study. The antenna showed optimal performance around the second resonance frequency and exhibited different total efficiency and bandwidth on various semi-infinite substrates. The loop antenna presented higher efficiency and bandwidth compared to graphene dipole antenna.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2021)
Article
Optics
Ushaben Keshwala, Sanyog Rawat, Kanad Ray
Summary: The article presents the design and detailed analysis of a DNA-shaped antenna for terahertz and sub-terahertz applications, which achieves dual-band characteristics with enhanced bandwidth by changing the ground from full to partial.
Article
Chemistry, Analytical
Moon-Jeong Lee, Ha-Neul Lee, Ga-Eun Lee, Seong-Tae Han, Jong-Ryul Yang
Summary: This paper proposes a CMOS detector for high-quality images in the sub-terahertz region, and verifies its design and performance. By adding a cross-coupling capacitor and using common source operation, the detector improves the output-signal coupling characteristics. The experimental results demonstrate that the proposed detector achieves excellent detection performance at high frequencies, resolving narrower line widths, and achieving a higher signal-to-noise ratio for THz imaging.
Article
Optics
Guozhen Zhang, Qirui Fang, Ying Li, Jun Yang, Minggang Hu, Jian Li, Guangsheng Deng, Zhiping Yin, Hongbo Lu
Summary: This paper presents a novel sub-terahertz liquid crystal (LC) phase shifter based on digital coding metasurfaces. The proposed structure changes the state of the phase shifter by switching the voltage on every grating, allowing the deflection of LC molecules within a subregion. Four switchable coding states of the phase shifter are obtained experimentally. This work provides a novel idea for wavefront modulation of phase.
Article
Optics
Shu-Ling Cheng, Hong-Wei Wu, Wen-Jun Sun, Nong Zhou, Cheng-Yao Peng, Zong-Qiang Sheng, Wen-Bing Zhang
Summary: In this paper, remote non-radiative terahertz wireless power transfer is achieved using self-resonating subwavelength spoof plasmonic structures, while minimizing the impact on the surrounding electromagnetic environment. The resonating frequency and quality factor of the magnetic dipole mode can be adjusted by tailoring the geometric structure.
Article
Optics
Sergey Bodrov, Aleksey Murzanev, Aleksey Korytin, Andrey Stepanov
Summary: The study introduces a novel graphene-based terahertz-field-induced optical luminescence (GB-TFIOL) technique for near-field mapping, demonstrating its application in visualizing local terahertz-field enhancement through experimental proof-of-principle.
Article
Optics
Mohammad M. Fakharian
Summary: The graphene-based antenna designed in this paper is multi-functional and can be tuned for frequency, polarization, and radiation direction by adjusting the gate voltage. It can replace multiple traditional antennas, reducing size and cost while improving performance.
Article
Engineering, Electrical & Electronic
Tian Liu, Wen Jian Zhu, Xiao Jian Hu, Liang Hua Ye, Duo-Long Wu
Summary: This letter introduces a dual-wideband dual-polarized magnetoelectric dipole antenna that operates at the prominent frequency bands of 1.7-2.7 GHz and 3.3-5.0 GHz in Sub-6 GHz. The antenna design includes a cross ME dipole for dual-polarized radiation and a cross strip with a notched band. Additional features like a cross patch and a metal baffle improve impedance matching and stability. The measured results demonstrate the antenna's dual-wideband and dual-polarized characteristics, making it suitable for base-station applications in Sub-6 GHz.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2023)
Review
Chemistry, Multidisciplinary
Mikhail Tarasov, Aleksandra Gunbina, Artem Chekushkin, Vyacheslav Vdovin, Aleksei Kalaboukhov
Summary: Integrated quasi-optical cryogenic terahertz receivers consist of various components such as detectors, filters, interferometers, and metamaterials, which were fabricated and experimentally studied on the same platform. These components were designed using different numerical simulation methods, with filters utilizing periodic frequency-selective surfaces and detector arrays requiring a complete analysis of the finite structure. The spectral characteristics of the filters, interferometers, and antenna arrays were measured in the frequency range of 50-600 GHz.
APPLIED SCIENCES-BASEL
(2021)
Article
Engineering, Electrical & Electronic
Saeid Gholami, Ali Bahari
Summary: By adding spiral lines to the electrodes of photoconductive dipole antennas, this paper increases the intensity and frequency peak of terahertz radiation. This change improves the effectiveness of the radiation output and is crucial for enhancing radiation efficiency.
OPTICAL AND QUANTUM ELECTRONICS
(2021)
Article
Multidisciplinary Sciences
Jun-ichi Sugiyama, Yuji Tokunaga, Mafumi Hishida, Masahito Tanaka, Koh Takeuchi, Daisuke Satoh, Masahiko Imashimizu
Summary: This study investigates the collective dynamics of protein and water molecules in the sub-terahertz frequency region and their influence on the chemical processes in protein-water systems. The results show that sub-terahertz irradiation gradually decreases the dielectric permittivity of the protein solution by reducing the polarization of water molecules. These findings are important for studying hydration-mediated protein functions based on sub-terahertz irradiation.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Zhao Jin, Yu Rong, JingDong Yu, Fei Wu
Summary: This paper presents the design of a terahertz dipole antenna with compound reconfigurability, allowing control over frequency, radiation pattern, and polarization state. By applying a capacitive load loop (CLL) made of graphene-metal composite material around a pair of orthogonal graphene-based dipole antennas and adjusting the bias voltage, the surface conductivity of graphene can be controlled to achieve compound reconfigurability. The graphene strips on the CLL provide flexibility in radiation characteristics. The operating frequency of the antenna can be reconfigured within the range of 1.40 to 1.84 THz by adjusting the combination of chemical potentials of graphene. Additionally, directional radiation with four beams (0°, 90°, 180°, 270°) in the XOY plane at 1.75 THz can be achieved, and RHCL or LHCL can be controlled within the range of 1.68 to 1.81 THz.
Article
Engineering, Electrical & Electronic
Reza Yazdani, Hadi Aliakbarian, Amir Sahraei, Guy A. E. Vandenbosch
Summary: This study presents a novel high-efficiency shared-aperture triple-band dipole array antenna configuration for base station applications, which can achieve stable radiation patterns. Experimental results confirm the stable radiation patterns and impedance bandwidths across three frequency bands, making it a promising candidate for future 5G developments.
IET MICROWAVES ANTENNAS & PROPAGATION
(2021)
Article
Engineering, Electrical & Electronic
Yang Cheng, Yuandan Dong
Summary: The proposed antenna features a novel design that allows for circular polarization radiation in different frequency bands, including both low and high frequencies. It shows excellent bandwidth and gain performance, making it suitable for applications in 5G and other communication systems.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Hsin-Hui Huang, Saulius Juodkazis, Eugene G. Gamaly, Vladimir T. Tikhonchuk, Koji Hatanaka
Summary: This study analyzes the processes produced by the interaction of two subsequent ultra-short laser pulses with a water flow, and finds that this interaction generates strong THz pulses and enhanced X-ray emission. It is demonstrated that these emissions are produced by the interaction of a main laser pulse with liquid water ejected from the surface by a pre-pulse, resulting in the acceleration of energetic electron beams. This scheme enables efficient energy conversion in THz pulses.
Article
Optics
Chunxu Chen, Kelson Kaj, Xiaoguang Zhao, Yuwei Huang, Richard Averitt, Xin Zhang
Summary: Metasurfaces have shown great potential in controlling electromagnetic waves using arrays of subwavelength resonators. In this study, a mechanically reconfigurable metasurface based on a microelectromechanical system (MEMS) is presented for dynamic surface wave switching at terahertz frequencies. The metasurface allows for efficient conversion between plane waves and surface waves with a wide working bandwidth. This technology has applications in spatial light modulation, beam steering, focusing, and beam combining for future communication systems.
Article
Nanoscience & Nanotechnology
Ke Wu, Guangwu Duan, Xiaoguang Zhao, Chunxu Chen, Stephan William Anderson, Xin Zhang
Summary: RFID technology is widely used in industrial applications for tracking and tracing products, assets, and material flows. The trend towards miniaturized RFID sensor tags continues to advance, but presents challenges for communication coverage area. Recent efforts have focused on using metamaterials to increase power transfer efficiency in RFID systems. Applying magnetic metamaterials and local field enhancement package to near-field RFID technology offers high power transfer efficiency and larger communication coverage area, creating new opportunities in the emerging Internet of Things era.
MICROSYSTEMS & NANOENGINEERING
(2022)
Article
Nanoscience & Nanotechnology
Samuel H. Kann, Erin M. Shaughnessey, Jonathan R. Coppeta, Hesham Azizgolshani, Brett C. Isenberg, Else M. Vedula, Xin Zhang, Joseph L. Charest
Summary: This study integrates optical-based oxygen sensors in a high-throughput organ-on-chip platform to monitor the metabolic activity of cells in membrane bilayer devices. By measuring oxygen changes in real-time and estimating cell oxygen consumption rates using a finite element analysis model, metabolic shifts in human renal proximal tubule cells following exposure to different drugs were successfully detected.
MICROSYSTEMS & NANOENGINEERING
(2022)
Article
Physics, Applied
Ao Chen, Xiaoguang Zhao, Zhiwei Yang, Stephan Anderson, Xin Zhang
Summary: Ventilated acoustic insulation, based on labyrinthine metamaterials, is a promising research direction in applied acoustics. The proposed design shows potential for high-performance wide-band acoustic insulation and ventilation. The design achieves effective soundproofing in the frequency range and provides a foundation for the development of broadband ventilated acoustic insulators.
PHYSICAL REVIEW APPLIED
(2022)
Article
Physics, Applied
Yuwei Huang, Xuefei Wu, Jacob Schalch, Guangwu Duan, Chunxu Chen, Xiaoguang Zhao, Kelson Kaj, Hai-Tian Zhang, Roman Engel-Herbert, Richard D. Averitt, Xin Zhang
Summary: By integrating with dynamic quantum materials like vanadium dioxide (VO2), tunable metamaterials can be created for high-performance devices in challenging applications. The symbiotic integration of metamaterial arrays with quantum materials enhances the modulation amplitude and reveals a redshift in the resonant frequency during the insulator-to-metal transition (IMT).
PHYSICAL REVIEW APPLIED
(2022)
Article
Optics
Xiaoyue Zhou, Yuchen Lin, Yi Chan, Fu Deng, Jingdi Zhang
Summary: This article reports on a proof-of-principle experiment that generates carrier-envelope phase (CEP)-controllable and frequency-tunable narrowband terahertz (THz) radiation from an air-plasma filament using the beat of a temporally stretched two-color laser pulse sequence. The pulse sequence was prepared by passing the ultrafast laser pulse through a grating stretcher and Michelson interferometer with adjustable inter-arm delay. By partially frequency-doubling and focusing the pulse sequence, an air-plasma filament emitting a THz wave with desired pulse characteristics (center frequency and CEP) was created under coherent control. Numerical simulations were performed to replicate the experimental results and elucidate the complex nonlinear light-matter interaction. This work demonstrates the feasibility of generating coherently controlled narrowband THz waves with high tunability in laser-induced air plasma.
Editorial Material
Chemistry, Physical
Richard D. Averitt
Summary: Circularly polarized photoexcitation induces the formation of spin domains in polycrystalline halide perovskite films with strong spin-orbit coupling and local inversion symmetry breaking, as observed by ultrafast optical microscopy.
Article
Materials Science, Multidisciplinary
Yuwei Huang, Kelson Kaj, Chunxu Chen, Zhiwei Yang, Richard D. Averitt, Xin Zhang
Summary: Bound states in the continuum (BIC) is an exotic concept describing systems without radiative loss. This study introduces a structurally tunable BIC terahertz metamaterial fabricated using micromachining and characterized using terahertz time domain spectroscopy. The bending angle of the metamaterial is controlled by thermal actuation to modify the capacitance and achieve tuning from a quasi-BIC state to the BIC state. Temporal coupled mode theory (CMT) is used to gain additional insight into the tunable electromagnetic response of the metamaterial.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Physics, Applied
Ao Chen, Zhiwei Yang, Xiaoguang Zhao, Stephan Anderson, Xin Zhang
Summary: We propose a composite acoustic metamaterial consisting of Mie resonators and a Helmholtz resonator array, which achieves a broadband acoustic attenuation in the low-frequency regime. The wideband soundproofing effect is explained using the transfer-matrix method and the lumped-element model, and the transmission loss and transmittance are tested numerically and experimentally. By using a deep-subwavelength structure, our composite design successfully blocks over 90% of incident acoustic energy within a frequency range of 1250 Hz, offering a design paradigm for extraordinary airborne acoustic silencing in low-frequency regimes.
PHYSICAL REVIEW APPLIED
(2023)
Article
Materials Science, Multidisciplinary
Xia Zhu, Ke Wu, Stephan W. Anderson, Xin Zhang
Summary: Signal-to-noise ratio (SNR) is an important metric for assessing MRI image quality. This study proposes a Helmholtz coil-inspired volumetric wireless resonator that can significantly enhance SNR. Experimental results show that the SNR can be boosted by 5 times or more in the region covering the human knee. This research offers an efficient and practical wireless solution for improving MRI image quality, with potential applications in various imaging fields.
ADVANCED MATERIALS TECHNOLOGIES
(2023)
Article
Chemistry, Analytical
Samuel H. Kann, Erin M. Shaughnessey, Xin Zhang, Joseph L. Charest, Else M. Vedula
Summary: Monitoring steady state oxygen levels in a high-throughput organ-on-chip platform with integrated optical-based oxygen sensors can evaluate drug-induced nephrotoxicity in a human microfluidic co-culture model of the kidney proximal tubule. The study demonstrates the dose and time-dependent injury responses of human PT cells to cisplatin using oxygen consumption measurements in the platform. The results highlight the utility of steady state oxygen measurements as a rapid, non-invasive, and kinetic readout of drug-induced injury in high-throughput microfluidic kidney co-culture models.
Correction
Engineering, Electrical & Electronic
Kebin Fan, John Koulakis, Karoly Holczer, Seth Putterman, Willie J. Padilla
JOURNAL OF INFRARED MILLIMETER AND TERAHERTZ WAVES
(2022)
Article
Materials Science, Multidisciplinary
V. A. Stoica, D. Puggioni, J. Zhang, R. Singla, G. L. Dakovski, G. Coslovich, M. H. Seaberg, M. Kareev, S. Middey, P. Kissin, R. D. Averitt, J. Chakhalian, H. Wen, J. M. Rondinelli, J. W. Freeland
Summary: This study used ultrashort X-ray pulses to investigate the structural and magnetic dynamics of the nickelate model NdNiO3 under photoexcitation. The experiments revealed the ultrafast quenching of magnetic order and the delayed collapse of the insulating phase during the photoinduced insulator-to-metal transition. It was found that both the magnetic and structural degrees of freedom contribute to driving the transition.
