Article
Optics
Lianzhong Jiang, Kin Seng Chiang
Summary: We demonstrate all-optical mode switching using a graphene-buried polymer waveguide asymmetric directional coupler. The device utilizes the photothermal effect of graphene to achieve efficient switching between different modes. The graphene-buried polymer waveguide offers potential for low-power all-optical control devices.
Article
Physics, Applied
Yi-An Wei, Pei-Jung Wu, Po-Yu Tsai, Kuen-Lin Chen, Chan-Shan Yang
Summary: This study presents experimental and theoretical evidence of the Mie resonance effect in the terahertz range using Fe3O4/Kerosene ferrofluid. The complex refractive indices at 0.5 THz were found to change significantly and rapidly with an increase in magnetic field strength. A prominent absorption peak at 0.5 THz was observed in transmittance and absorption measurements, corresponding to a magnetic field intensity of 178.0 mT. This phenomenon can be attributed to the adjustment of particle spacing, leading to resonance under different magnetic field conditions. These findings hold great potential in advancing the development of magneto-optical THz modulators for imaging and communication applications.
APPLIED PHYSICS LETTERS
(2023)
Article
Computer Science, Information Systems
Qinghe Zhuang, Feng Yan, Zhengfeng Xiong, Meng Yang, Min Liu
Summary: This paper presents a novel high-power rotary waveguide phase shifter based on circular polarizers specifically engineered for high-power microwave (HPM) applications. The phase shifter is capable of performing a precise 360 degree linear phase shift through rotation and consists of three parts: a linearly polarized to left-handed circularly polarized (LP-LHCP) mode converter, a left-handed to right-handed circularly polarized (LH-RHCP) mode converter, and a linearly polarized to right-handed circularly polarized (LP-RHCP) mode converter. The paper analyzes the phase-shifting principle, optimizes the three parts of the X-band rotary waveguide phase shifter, and conducts simulation studies on the entire phase shifter, which is made of aluminum. The results show good performance in terms of reflection, insertion loss, and phase shift within the frequency range.
Article
Optics
Lianzhong Jiang, Quandong Huang, Kin Seng Chiang
Summary: We propose a low-power all-optical switch based on a graphene-buried balanced Mach-Zehnder interferometer structure. The switch operates by using the heat generated from graphene's absorption of the pump light to switch the signal light. Experimental results show high pump absorption and low signal loss in the fabricated device, allowing for efficient signal switching with minimal sensitivity to temperature variations.
Article
Engineering, Electrical & Electronic
Reza Karimian, Sajjad Taravati, Mansoor Dashti Ardakani, Shahrokh Ahmadi, Mona E. Zaghloul
Summary: This study introduces a nonreciprocal-beam phased-array antenna that provides power amplification in both transmission and reception states. Compared to other antenna designs, this antenna does not introduce undesired time harmonics and frequency conversion, and does not require an RF bias signal.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2021)
Article
Optics
Li-Yuan Chiang, Chun-Ta Wang, Steve Pappert, Paul K. L. Yu
Summary: We present a passively biased 2 x 2 thermo-optic switch with high power efficiency and fast response time. The switch utilizes the highly concentrated optical field of a slot waveguide mode and the strong thermo-optic effect of a nematic liquid crystal (NLC) cladding. The device demonstrates low power consumption and fast operation speed, providing a new solution for designing thermo-optic actuators.
Article
Engineering, Electrical & Electronic
Hassan Abdollahy, Ali Farahbakhsh, Mohammad Hossein Ostovarzadeh
Summary: This paper presents a reconfigurable phase shifter based on gap waveguide technology, where the phase shift is controlled by adjusting the width of the waveguide. The simulation and measurement results show an impedance bandwidth of about 34.5%, a maximum insertion loss of 0.6 dB, and a maximum phase shift of 524 degrees.
AEU-INTERNATIONAL JOURNAL OF ELECTRONICS AND COMMUNICATIONS
(2021)
Article
Computer Science, Information Systems
Ali Karami Horestani, Zahra Shaterian, Michal Mrozowski
Summary: This research focuses on the design and realization of high-performance high-power variable phase shifters using groove gap waveguide technology. It is demonstrated that the unique characteristic of groove gap waveguides, which allows proper operation without electrical connection, can be utilized to design mechanically tunable devices. A mechanically tunable cavity resonator and phase shifters with a wide range of achievable phase shifts are proposed. A phase shifter with 540 degrees relative phase shift at 15 GHz is designed, fabricated, and measured to validate the concept. Additionally, a multi-layer version of the proposed phase shifter with stationary feed ports and improved performance is presented.
Article
Materials Science, Multidisciplinary
Kai Xu, Bao Yue Zhang, Yihong Hu, Muhammad Waqas Khan, Rui Ou, Qijie Ma, Chunmei Shangguan, Billy J. Murdoch, Weijian Chen, Xiaoming Wen, Guanghui Ren, Jian Zhen Ou
Summary: Researchers have achieved an all-optical on-chip switch using 2D ultrathin Ga2S3, which is controlled by visible light excitation. The switch operates at an extremely small optical power density and exhibits fast response and recovery times.
JOURNAL OF MATERIALS CHEMISTRY C
(2021)
Article
Optics
Chun-Wang Liu, Ye Liu, Lei Du, Wan-Jun Su, Huaizhi Wu, Yong Li
Summary: In this article, we study the enhanced sensing of optomechanically induced nonlinearity (OMIN) in a cavity-waveguide coupled system. By introducing weak waveguide-mediated coherent coupling, we find a strong bistable response of the cavity intensity to the OMIN near the cavity resonance. This enhanced sensitivity, measured by an enhancement factor, is resistant to cavity decay and fluctuations in the cavity-waveguide detuning.
Article
Engineering, Electrical & Electronic
Qingxiang Dong, Yongle Wu, Zuoyu Xu, Weimin Wang, Qinghua Yang
Summary: This article presents miniaturized dual-band dielectric waveguide (DW) filters and phase shifter based on multimode resonator (MMR). The shape of the MMR, chosen as a cube, allows for a miniaturized structure. Through the analysis of a single MMR, dual-band working is achieved in the proposed dielectric filters. The designed, manufactured, and measured examples of two MMRs demonstrate good agreement between measured, theoretical, and simulated results. The improved filter shows excellent filtering function in both frequency bands with good out-of-band performance. Lastly, the two DW filters are employed to compose a dual-band phase shifter.
AEU-INTERNATIONAL JOURNAL OF ELECTRONICS AND COMMUNICATIONS
(2023)
Article
Chemistry, Analytical
Wei Zhang, Jin Shi, Gangxiong Wu, Longlong Lin, Kai Xu
Summary: This paper proposes a slotted substrate integrated waveguide (SIW) to achieve a wideband common-mode (CM) suppression phase shifter. Differential-mode (DM) impedance matching and CM suppression are realized by utilizing the characteristics of TE20 mode and TE10 (TE30) mode. Wideband phase shift and low phase deviation are achieved through the counteraction of the slot and the delay line. Compared to existing technologies, the proposed method offers advantages in terms of wideband CM suppression, wide phase shift range, and simple structure. Five prototypes are designed with different frequency ranges and achieve satisfactory performance in terms of insertion loss, return loss, and CM suppression bandwidth.
Article
Engineering, Electrical & Electronic
Daniel Sanchez-Escuderos, Jose Ignacio Herranz-Herruzo, Miguel Ferrando-Rocher, Alejandro Valero-Nogueira
Summary: This article introduces a novel all-metal mechanical phase shifter in gap waveguide technology to provide beam-scanning capabilities to conventional slot array antennas. Experimental results validate the effectiveness of the proposed concept, achieving significant steering angles and high gain levels.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2021)
Article
Optics
Yutao Bo, Chunying Guan, Rang Chu, Tailei Cheng, Li Xu, Lu Liu, Jing Yang, Jinhui Shi, Pengfei Wang, Jun Yang, Libo Yuan
Summary: The study presents an all-fiber thermo-optic modulator based on a side-polished twin-core fiber Michelson interferometer coated with NaNdF4 nanoparticles for optical switching. The device shows a significant modulation phase shift near the wavelength of 1260 nm and fast rise (fall) times of 152 (50) ms. With its compact structure and strong robustness, the proposed device has great potential for applications in optical modulators.
Article
Physics, Applied
R. Alcorta Galvan, C. Croenne, B. Dubus, B. Loiseaux, E. Eustache, M. Bertrand, A. -c. Hladky-Hennion
Summary: This study presents a new solution for achieving tunable surface acoustic wave (SAW) components based on the electrical Bragg band gap concept. The concept is validated on a SAW resonator on a LiNbO3 substrate, showing that the main resonance frequency can be shifted by modifying the electrical condition on the cavity's mirrors.
APPLIED PHYSICS LETTERS
(2022)