Article
Optics
Tanmay Bhowmik, Bhairov Kr. Bhowmik, Pranav Kr. Pandey, Gagan Kumar, Debabrata Sikdar
Summary: By engineering meta-atoms, tunable metamaterials have opened up new possibilities for active control of light absorption. In this study, a broadband electrically-tunable metamaterial absorber is proposed for simultaneous modulation of reflected light amplitude in the O-band and C-band. Through the coupling of gap plasmon resonance and epsilon-near-zero phenomenon, real-time control of reflected light amplitude is achieved. The proposed metamaterial absorber demonstrates more than 80% absorption over a 370 nm spectral window and allows for amplitude modulation with high extinction ratios at specific wavelengths.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Yuya Yamaguchi, Pham Tien Dat, Shingo Takano, Masayuki Motoya, Shotaro Hirata, Yu Kataoka, Junichiro Ichikawa, Satoshi Oikawa, Ryo Shimizu, Naokatsu Yamamoto, Kouichi Akahane, Atsushi Kanno, Tetsuya Kawanishi
Summary: An electro-optic frequency-domain equalizer is proposed and investigated to increase the 3-dB bandwidth of optical modulators. The equalizer can be integrated with conventional modulators using different waveguide structures. Experimental results show that integrating the equalizer can double the modulator's 3-dB bandwidth.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Polymer Science
Benedict Wen-Cheun Au, Kah-Yoong Chan, Gregory Soon How Thien, Mian-En Yeoh, Mohd Zainizan Sahdan, Hanabe Chowdappa Ananda Murthy
Summary: Over the past few decades, the research on electrochromism has focused on altering the optical transmittance of electrochromic (EC) materials using a small applied voltage. Tungsten oxide (WO3) is commonly used in EC devices (ECDs) to achieve this effect. In this study, WO3 films were produced using a sol-gel spin-coating method, and the influence of various transparent conducting oxides (TCOs) on the construction of ECDs was investigated. The combination of fluorine-doped tin oxide (FTO) and indium-doped tin oxide (ITO) as the TCO and counter electrode, respectively, exhibited the highest coloration efficiency.
Article
Optics
Hosein Ghobadi, Herman L. Offerhaus, Jose A. Alvarez-Chavez, Monica Morales-Masis, Israel De Leon
Summary: Transparent Conducting Oxides (TCOs) in the Epsilon-Near-Zero (ENZ) spectral region exhibit a large and ultrafast intensity-dependent refractive index, which is highly dependent on material properties and measurement conditions. This study demonstrates that extensive nonlinear optical measurements can be avoided by analyzing the material's linear optical response. By considering thickness-dependent material parameters, the impact on absorption and field intensity enhancement under different measurement conditions can be determined, allowing for optimization of the nonlinear response. Experimental measurements of Indium-Zirconium Oxide (IZrO) thin films with varying thicknesses confirm the agreement between experiment and theory, and show that film thickness and excitation angle can be adjusted simultaneously for optimizing the nonlinear optical response, enabling flexible design of highly nonlinear TCO-based optical devices.
Article
Chemistry, Physical
Yao Xiong, Fu Chen, Yongzhi Cheng, Hui Luo
Summary: A transparent multilayer metamaterial absorber (MMA) with broadband microwave absorption characteristics based on Indium Tin Oxide (ITO) and polymethyl methacrylate (PMMA) has been designed and fabricated. By adjusting the resistance of ITO and the structural parameters, the microwave absorption properties can be controlled and achieve more than 90% absorption in the frequency range of 2.64-18 GHz. The microwave attenuation mechanism, angle-sensitive properties, and visible light transmittance were investigated, and the experimental and simulated results are consistent, indicating the potential application of this absorber in transparent microwave absorption.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Physics, Applied
Guangsheng Deng, Kun Lv, Hanxiao Sun, Jun Yang, Zhiping Yin, Baihong Chi, Xiangxiang Li
Summary: An ultra-broadband and polarization-insensitive metamaterial absorber with high optical transparency is proposed in this work, showing excellent absorption performance and stability for electromagnetic applications.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Optics
Tianhang Lian, Kaidi Yang, Shijie Sun, Mu Zhu, Jian Yue, Baizhu Lin, Xiaoqiang Sun, Xibin Wang, Daming Zhang
Summary: A polarization-independent electro-absorption modulator based on trapezoid polymer-graphene waveguide is proposed. By applying different gate voltages on the graphene layers, polarization-independent modulation is achieved. Simulation and optimization results show a compact size and high extinction ratio for the modulator.
OPTICS AND LASER TECHNOLOGY
(2022)
Article
Physics, Applied
Huangyan Li, Youyi Feng, Hang Yuan, Minxin Zhao, Yi Wang, Qunsheng Cao, Filippo Costa
Summary: A reconfigurable absorber/reflector, based on structured water medium, has been developed. It exhibits optical transparency, broadband switching function, and temperature stability, making it a promising candidate for transparent smart windows in large-scale ground-based stealth systems.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Chang Yang, Huicong Chang, Lin Xiao, Yanchen Qu
Summary: In this study, a transparent and broadband microwave metamaterials absorber with high absorption rate and transparency in visible and NIR spectrum was designed and fabricated. The absorber showed excellent performance in various angles and frequencies. Compared with traditional absorbers, this absorber has a wider range of applications.
Article
Engineering, Electrical & Electronic
Saheer Cheemadan, M. C. Santhosh Kumar
Summary: This study deposited CdO:ZnO composite thin films with varying compositions on glass substrates using RF magnetron sputtering. The optoelectronic characteristics of the films and their dependence on substrate temperature were investigated. The structural, electrical, morphological, and optical properties of the films were analyzed using various techniques. The results showed that all films had an average optical transmittance above 80% in the visible range, regardless of the deposition temperature and composition. The CdO:ZnO (70:30) composite thin films deposited at 200℃ exhibited the lowest electrical resistivity and a high carrier concentration. Increasing the substrate temperature from room temperature to 200℃ resulted in an increase in carrier mobility. The energy band gap values of the films were calculated based on the transmittance spectra.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2022)
Article
Materials Science, Multidisciplinary
Yanhua Xu, Jianbo Li, Jing Huang, Yuan He, Xiao Liu, Lupeng Zhao, Guodong Chen, Lili Miao
Summary: Low dimensional perovskite materials have attracted great attention as a highly promising class of functional materials for semiconductor optoelectronic applications. In this study, we reported the nonlinear absorption of low dimensional perovskite PEA2PbI4 and transparent conducting oxide material Aluminum-doped zinc oxide (AZO) within the telecommunications spectral window. We then fabricated all-optical diodes with a non-reciprocity factor of 10.1 dB based on the reverse saturable absorber (PEA2PbI4) and the saturable absorber (AZO). The results demonstrate the potential applications of perovskite-based materials in all-optical diodes and pave the way for the development of high-performance photonic devices.
RESULTS IN PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Yao Xiong, Fu Chen, Yongzhi Cheng, Hui Luo
Summary: In this study, a broadband and optically transparent metamaterial absorber was successfully designed and prepared. It exhibited high microwave absorption efficiency at various angles and polarizations, while maintaining good transparency to visible light. The excellent performance and potential of this metamaterial absorber provide new possibilities for the development of transparent microwave absorbing windows and devices.
Article
Chemistry, Physical
Salih Ozbay, Nursev Erdogan, Fuat Erden, Merve Ekmekcioglu, Busra Rakop, Mehtap Ozdemir, Gulnur Aygun, Lutfi Ozyuzer
Summary: ITO, ZTO, AZO, and Ag are commonly used in multilayer thin films of transparent conducting oxide (TCO)/metal/TCO electrodes, with critical knowledge of surface free energy (SFE) being important for designing desirable TCO-based sandwich structures. Contact angle measurements of different liquids were used to evaluate the wettability properties of TCO, Ag interlayer, and TCO/Ag/TCO. The results showed that the SFE components varied depending on the TCO type, the total SFE values of TCO/Ag/TCO films were lower than TCO films, and AZO/Ag adhesion was stronger than other TCO/Ag structures.
APPLIED SURFACE SCIENCE
(2021)
Article
Engineering, Electrical & Electronic
Weihao Lin, Siming Sun, Li-Yang Shao, Mang Vai, Perry Ping Shum, Yuhui Liu, Weizhi Wang
Summary: A new tunable electro-optical and thermal-optical modulator based on a liquid crystal-filled side hole fiber in a fiber ring laser system has been proposed, offering high sensitivity and good performance. The sensor is capable of effectively monitoring temperature changes and electric fields, making it suitable for wavelength-tunable electro-optical devices within a small temperature change range.
IEEE SENSORS JOURNAL
(2021)
Article
Materials Science, Multidisciplinary
Naveen Kumar, Muhammad Kumail, Junghyun Lee, Hyeong Gi Park, Joondong Kim
Summary: In this study, a self-powered transparent photodetector consisting of a vdW semiconductor (SnS) and a wide-bandgap oxide (Ga2O3) thin film was successfully fabricated. The device is highly transparent with an average visible transmittance of 45%. Under illumination, the self-biased transparent photodetector exhibits photovoltaic behavior, with a significant open circuit voltage of 496 mV and a considerably high short-circuit current density of 1.7 mA/cm^2. The device shows a significant photoresponse from UV (340 nm) to NIR (850 nm) illumination, with a remarkable responsivity of 210.4 mA/W and the fastest response time of approximately 8 ms, making it a self-operated broadband transparent photodetector.
MATERIALS RESEARCH BULLETIN
(2023)
