We propose a bidirectional terahertz (THz) spectrum splitter using a practically simple metamaterial structure consisting of rectangular grooves covered by graphene. Thanks to the graphene optoelectronic tunability and by adjusting the grooves width, this structure provides nearly 2π phase shift. At the same time, the reflection efficiency is acceptable throughout the phase shifts. We design each of the meta-atoms using a circuit model, and then we synthesize the final supercell based on the generalized Snell's law so that the structure reflects different frequency waves to totally different directions. The full-wave simulations demonstrate the beam splitting with a remarkable efficiency of around 80%.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1364/OL.42.004808 | DOI Listing |
Photoacoustics
February 2025
Key Laboratory of Micro-Inertial Instrument and Advanced Navigation Technology Ministry of Education, School of Instrument Science and Engineering, Southeast University, Nanjing 210096, China.
The quartz tuning fork (QTF) being the acoustic-electrical conversion element for quartz-enhanced photoacoustic spectroscopy (QEPAS) system directly affects the detection sensitivity. However, the low electromechanical conversion efficiency characteristic of standard QTF limits the further enhancement of the system. Therefore, the optimized design for QTF is becoming an important approach to improve the performance of QEPAS.
View Article and Find Full Text PDFPolymers (Basel)
September 2024
Laboratory of Reinforced Concrete and Seismic Design of Structures, Civil Engineering Department, School of Engineering, Democritus University of Thrace, 67100 Xanthi, Greece.
The fiber-reinforced polymer (FRP) strengthening of reinforced concrete (RC) elements with torsional deficiencies has not yet been extensively studied. Existing studies have primarily focused on rectangular RC beams. The few studies on L or T-shaped beams have used open-form retrofitting methods.
View Article and Find Full Text PDFMicromachines (Basel)
August 2024
School of Electro-Mechanical Engineering, Guangdong University of Technology, Guangzhou 510006, China.
Nanogrooves with high aspect ratios possess small size effects and high-precision optical control capabilities, as well as high specific surface area and catalytic performance, demonstrating significant application value in the fields of optics, semiconductor processes, and biosensing. However, existing manufacturing methods face issues such as complexity, high costs, low efficiency, and low precision, especially in the difficulty of fabricating nanogrooves with high resolution on the nanoscale. This study proposes a method based on focused ion beam technology and a layer-by-layer etching process, successfully preparing V-shaped and rectangular nanogrooves on a silicon dioxide substrate.
View Article and Find Full Text PDFMicromachines (Basel)
July 2024
School of Mechanical Engineering, North University of China, Taiyuan 030051, China.
Preparing elastic substrates as a carrier for dual-end supported nickel chromium thin film strain sensors is crucial. Wet etching is a vital microfabrication process widely used in producing microelectronic components for various applications. This article combines lithography and wet etching methods to microprocess the external dimensions and rectangular grooves of 304 stainless steel substrates.
View Article and Find Full Text PDFUltrason Sonochem
October 2024
College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, Shandong, China. Electronic address:
Hydrodynamic cavitation reactors are of great promise for the applications of chemical process intensification and water treatment. In this work, a novel cylindrical rotational hydrodynamic cavitation reactor (CRHCR) with rectangular grooves and oblique tooth protrusions on the rotor surface was studied. The three-dimensional characterization of cavitation within the CRHCR was observed from the front and left views by the high-speed camera experiments.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!