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IEEE Asia-Pacific Conference on Antennas and Propagation (APCAP)

作者： Xiaodong An Jialong Xie Da Li Yudi Fan Erping Li The Zhejiang Key Laboratory of Advanced Micro/Nano Electronic Devices & Smart Systems and Applications Zhejiang University Hangzhou China

In this paper, a novel 3-dimensional (3-D) frequency selective surface (FSS) structure with ultrawide passband and high selectivity is proposed. Compared to traditional two-dimensional (2-D) wideband structures, (3-D) structures offer enhanced selectivity but exhibit higher insertion loss in the passband. Moreover, three-dimensional structures are often more complex and challenging to manufacture. This paper proposes a simplified three-layer structure. When vertically incident, the FSS exhibits a -3 dB bandwidth of 8-18.4 GHz with a relative bandwidth of 78.7%. Additionally, it forms a stopband with a suppression level exceeding -10 dB within the frequency range of 0-5.2 GHz. In the TE mode, the FSS maintains excellent operational performance within an incident angle range of 0-40 degrees.

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Rapid Detection Technology for Cocaine and Methamphetamine Acute Abuse based on EEG

Rapid Detection Technology for Cocaine and Methamphetamine A...

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2024 International Conference on Next Generation electronics and Photonics, INGEP 2024

作者： Xia, Jie Yuan, Hongwen Pan, Jiadong Li, Kan Zhang, Luxi Dong, Shurong Key Lab. of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang College of Information Science and Electronic Engineering Zhejiang University Hangzhou310027 China HangZhou City University Sports and Aesthetic Education Department Hangzhou310015 China Shanghai Institute of Satellite Engineering shanghai200240 China

Multi-domain characterization and a new fast detection method for acute illegal psychostimulants abuse detection based on waking-state EEG of mice is proposed in this paper. To get corftical electroencephalogram (EEG), three groups of mice were injected with cocaine (Coca), methamphetamine (Meth), and saline (Sali) respectively following the experimental paradigm of drug abuse. The EEG features were extracted out by multi-domain views, including time, frequency, complexity, dynamics, and independent domains to obtain acute drug abuse effects on the brain. New strategy combing time domain with frequency domain is developed as multi-domain input and by means of dimension transformation approach preserving temporal information, the performance of drug abuse detection is greatly improved with deep learning models of ResNet50. Results show that comparing to support vector machine (SVM), k nearest neighbor (kNN), random forest (RF), and long short-term memory fully convolutional networks (LSTM-FCN), Res-Net50 based on our proposed multi-domain features has best F1-score of 95.10%. This promising method provides a low-cost, fast, and widely assisted technology for psychostimulants abuse identification. © Published under licence by IOP Publishing Ltd.

关键词： Decision trees

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A Novel Four-Port Calibration Method for High Frequency On-Wafer S-parameter Measurement 15

A Novel Four-Port Calibration Method for High Frequency On-W...

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15th International Conference on microwave and Millimeter Wave Technology, ICMMT 2023

作者： Zhou, Jiefeng Zhang, Ling Chen, Junhui Li, Da Zhou, Ding Li, Er-Ping Zhejiang University College of Information Science and Electronic Engineering The Zhejiang Key Lab. of Advanced Micro/Nano Electronic Devices Smart Systems and Applications Hangzhou China High-Speed and High-Frequency Lab Huawei Technologies Co. Ltd Dongguan China

ISBN: (纸本)9798350338874

This paper proposes a novel four-port calibration method for on-wafer S-parameter measurement. Crosstalk terms can seriously deteriorate the measurement accuracy of high-frequency on-wafer systems. The proposed method can consider all error and crosstalk terms in on-wafer measurement using two ground-signal-signal-ground (GSSG) probes and ensure high calibration accuracy. Only six calibration standards are required to complete the four-port calibration by this method. The proposed method is verified by full-wave simulations up to 100 GHz. The simulation and calibration results are in great agreement, which proves the correctness and reliability of the proposed method. © 2023 IEEE.

关键词： Calibration

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Absorptive-Material-Based Structure for Suppressing Unwanted Radiation in Chip-Packages 13

Absorptive-Material-Based Structure for Suppressing Unwanted...

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13th Asia-Pacific International Symposium on Electromagnetic Compatibility and Technical Exhibition, APEMC 2022

作者： Xing, Jiaqi Liang, Xinglei Fan, Yudi Zhang, Ling Li, Da Li, Er-Ping Zhejiang University College of Information Science & Electronic Engineering ZJU-UIUC Institute The Zhejiang Key Lab. of Advanced Micro/Nano Electronic Devices Smart Systems and Applications Hangzhou China

ISBN: (数字)9781665416719

ISBN: (纸本)9781665416719

In this paper, a double-layer structured absorptive material for solving the electromagnetic radiation problems in chip-packages is proposed. This low-profile absorber structure is composed of two flat layers where the lower layer is made of absorbing material with high relative permittivity, while the upper layer is made of material with low relative permittivity to better meet the requirements of wide impedance matching. This structure is firstly designed based on theories and full-wave simulations. Then it is fabricated and applied to different absorbing materials working in the frequency range of 20-40GHz to suppress the radiation in a practical chip-package model. Finally, the effectiveness and universality of this structure are verified through measurements of the radiation suppression effect with different absorbing material settings. © 2022 IEEE.

关键词： Electromagnetic compatibility

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Breakdown of effective-medium theory by a photonic spin Hall effect

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Science China(Physics,Mechanics & Astronomy) 2023年第11期66卷 145-154页

作者： Shuaijie Yuan Xinxing Zhou Yu Chen Yuhan Zhong Lijuan Sheng Hao Hu Hongsheng Chen Ido Kaminer Xiao Lin Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Synergetic Innovation Center for Quantum Effects and ApplicationsSchool of Physics and ElectronicsHunan Normal UniversityChangsha410081China International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology Engineering Technology Research Center for 2D Material Information Function Devices and Systems of Guangdong ProvinceInstitute of Microscale OptoelectronicsShenzhen UniversityShenzhen518060China Interdisciplinary Center for Quantum Information State Key Laboratory of Extreme Photonics and InstrumentationZJU-Hangzhou Global Scientific and Technological Innovation CenterZhejiang UniversityHangzhou310027China International Joint Innovation Center Electromagnetics Academy at Zhejiang UniversityZhejiang UniversityHaining314400China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore639798Singapore Key Laboratory of Radar Imaging and Microwave Photonics Ministry of EducationCollege of Electronic and Information EngineeringNanjing University of Aeronautics and AstronauticsNanjing211106China Key Laboratory of Advanced Micro/Nano Electronic Devices&Smart Systems of Zhejiang Jinhua Institute of Zhejiang UniversityZhejiang UniversityJinhua321099China Shaoxing Institute of Zhejiang University Zhejiang UniversityShaoxing312000China Department of Electrical Engineering Technion-Israel Institute of TechnologyHaifa32000Israel

Effective-medium theory pertains to the theoretical modelling of homogenization,which aims to replace an inhomogeneous structure of subwavelength-scale constituents with a homogeneous effective *** effective-medium theory is fundamental to various realms,including electromagnetics and material science,since it can largely decrease the complexity in the exploration of light-matter interactions by providing simple acceptable ***,the effective-medium theory is thought to be applicable to any all-dielectric system with deep-subwavelength constituents,under the condition that the effective medium does not have a critical angle,at which the total internal reflection *** we reveal a fundamental breakdown of the effective-medium theory that can be applied in very general conditions:showing it for deep-subwavelength all-dielectric multilayers even without a critical *** finding relies on an exotic photonic spin Hall effect,which is shown to be ultrasensitive to the stacking order of deep-subwavelength dielectric layers,since the spin-orbit interaction of light is dependent on slight phase accumulations during the wave *** results indicate that the photonic spin Hall effect could provide a promising and powerful tool for measuring structural defects for all-dielectric systems even in the extreme nanometer scale.

关键词： photonic spin Hall effect effective-medium theory spin-orbit interaction of light

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Novel Surface Acoustic Wave Strain Sensor with Enhanced High-Temperature Performance and Resistance to Aging

Novel Surface Acoustic Wave Strain Sensor with Enhanced High...

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2023 International Congress on Ultrasonics, ICU Beijing 2023

作者： Zhang, Jikai Mu, Danyu Zhang, Zichao Jin, Hao Chen, Jinkai Xuan, Weipeng Dong, Shurong Luo, Jikui Zhejiang University Hangzhou310027 China Innovation and Research Institute of HIWING Technology Academy Beijing100074 China Zhejiang University Key Laboratory of Micro-nano Electronic Devices and Smart Systems of Zhejiang Province College of Information Science & Electronic Engineering Hangzhou310027 China Ministry of Education Key Laboratory of RF Circuits and Systems College of Electronics & Information Hangzhou Dianzi University Hangzhou310027 China Zhejiang University Key Laboratory of Collaborative sensing and autonomous unmanned systems of Zhejiang Province College of Information Science & Electronic Engineering Hangzhou310027 China

Surface acoustic wave (SAW) sensors based on Langasite (La3Ga5SiO14, LGS) have emerged as promising candidates for high-temperature strain measurement in passive wireless systems. However, limitations of strain transfer at temperatures above 800°C have hindered the repeatability of sensors due to temperature-induced effects. For instance, the aging of conventional high-temperature adhesives at elevated temperatures restricts the strain transfer between the measured object and the sensor. Moreover, materials like Inconel-600 exhibit a coefficient of thermal expansion significantly larger than the LGS, leading to thermal strains caused by thermal expansion mismatch beyond the maximum range of existing SAW strain sensors. Such factors increase the likelihood of sensor damage during a test. In this paper, we present a novel SAW sensor utilizing an ultra-thin LGS substrate encapsulated within a ceramic coating, which transfers strain by exerting pressure on both sides of the sensor. The strain sensor is mounted on an equal-strain beam inside a high-temperature furnace. The ceramic coating is not tightly bonded to the sensor, thereby mitigating the thermal expansion mismatch between the sensor and the beam at high temperatures. Furthermore, the ceramic coating can withstand large strain caused by thermal expansion while maintaining pressure on the sensor. This innovative SAW sensor enables repeat strain tests up to 800°C, including both calibration and formal tests. The measured strain exhibits an error of less than 5% compared to a standard strain gauge, demonstrating the sensor's enhanced performance and reliability. © 2024 Institute of Physics Publishing. All rights reserved.

关键词： Ceramic materials

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Driving deep-learning-based metasurface design with Kramers-Kronig relations

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Physical Review Applied 2024年第4期22卷 L041002页

作者： Guangfeng You Chao Qian Shurun Tan Erping Li Hongsheng Chen ZJU-UIUC Institute Interdisciplinary Center for Quantum Information State Key Laboratory of Extreme Photonics and Instrumentation ZJU-Hangzhou Global Science and Technology Innovation Center Key Laboratory of Advanced Micro/Nano Electronic Devices & Smart Systems of Zhejiang Jinhua Institute of Zhejiang University

Two-decade strides in metasurfaces have enabled a multitude of theoretical breakthroughs and experimental discoveries that outride established comprehension. Deep learning has recently found favor for expediting metasurface design and unearthing complex light-matter interactions, in contrast to resource-intensive numerical simulations. However, most “black box” algorithms lack enough discernment on parsing internal physical connections. Here, we propose a physical adversary channel to be complementary to gradient descent channel by embedding the Kramers-Kronig (KK) relations into a neural network, quantifying the inherent spectral contradictions at the output side. We evaluate the superiority of the KK-driven neural network in forward prediction and inverse metasurface design by modifying loss function and shaping probability distribution in latent space, respectively. The exceptional outcome suggests that the similarity between output and given spectra reaches up to 99.8% and maintains an extremely high fidelity even in a mutant band. Our work provides a physically explicable perspective to explain “black box” models, possibly reviving intelligent metasurface applications.

关键词： Inverse problems Artificial neural networks Metamaterials Metasurfaces Deep learning Electromagnetic wave theory

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Extended-localized transition in diffusive quasicrystals

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Physical Review Applied 2024年第6期21卷 064035-064035页

作者： Zhoufei Liu Pei-Chao Cao Ying Li Jiping Huang Department of Physics State Key Laboratory of Surface Physics and Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education) State Key Laboratory of Extreme Photonics and Instrumentation ZJU-Hangzhou Global Scientific and Technological Innovation Center International Joint Innovation Center Key Laboratory of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang The Electromagnetics Academy of Zhejiang University Shaoxing Institute of Zhejiang University

Compared with periodic systems, quasicrystals without translational invariance exhibit unexpected localization properties. The extended-localized transition in quasicrystals has been observed in both quantum and classical wave systems. However, its manifestation in diffusion systems, which serve as novel platforms for exploring phases of matter in condensed-matter physics, remains unexplored. Here we present an implementation of the extended-localized transition in a diffusive quasicrystal based on a coupled-ring chain structure. By modulating the thermal conductivities of the rings, we obtain the diffusive one-dimensional Aubry-André-Harper (AAH) model, which exhibits an extended-localized transition. Thanks to the ring-shaped chain, we clearly demonstrate the extended-localized transition under uniform excitation through temperature-field simulations. For the localized state, the temperature field clearly demonstrates a phenomenon of multiple localization centers, which has no counterpart in wave systems. We also quantitatively investigate the temperature evolution and size effect of this transition. Furthermore, local excitation is used to demonstrate the temperature field for both the extended state and the localized state. Besides, we implement the non-Hermitian diffusive AAH model by rotating the rings, whose temperature field shows a phenomenon of moving multiple localization centers in the localized phase. Finally, we give experimental suggestions for the diffusive AAH model and propose a potential application named the “double-trace distributed generator.” Our results should facilitate the design of flexible thermal devices and efficient heat management.

关键词： Anderson localization Diffusion Heat transfer Skin effect Thermoelectric effects Disordered systems Non-Hermitian systems Quasicrystals

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Revealing the Transformation Invariance of Full-Parameter Omnidirectional Invisibility Cloaks

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Electromagnetic Science 2023年第2期1卷 54-60页

作者： Bin Zheng Huan Lu Chao Qian Dexin Ye Yu Luo Hongsheng Chen Interdisciplinary Center for Quantum Information State Key Laboratory of Extreme Photonics and InstrumentationZJUHangzhou Global Scientific and Technological Innovation CenterZhejiang UniversityHangzhou 310027China International Joint Innovation Center The Electromagnetics Academy at Zhejiang UniversityZhejiang UniversityHaining 314400China Key Lab.of Advanced Micro/Nano Electronic Devices&Smart Systems of Zhejiang Jinhua Institute of Zhejiang UniversityZhejiang UniversityJinhua 321099China Shaoxing Institute of Zhejiang University Zhejiang UniversityShaoxing 312000China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore

Searching for an optimal solution among many nonunique answers provided by transformation optics is critical for many branches of research,such as the burgeoning research on invisibility *** past decades have witnessed rapid development of transformation optics,and different kinds of invisibility cloaks have been designed and ***,the available cloaks realized thus far have been mostly demonstrated with reduced parameters,which greatly impact the predefined cloaking ***,we report a general design strategy to realize full-parameter omnidirectional cloaks that can hide arbitrarily shaped objects in free *** approach combines a singular transformation with transformation-invariant *** cloaking device with extreme parameters is implemented using a metallic array *** the experiment,two cloak samples are designed and fabricated,one with nondiscrete cloaking regions and the other with separated hidden ***-unit transmission of electromagnetic waves with arbitrary incident angles is experimentally demonstrated along with significantly suppressed *** work challenges the prevailing paradigms of invisibility cloaks and provides deep insight into how transformation optics could be harnessed to obtain easily-accessible metadevices.

关键词： Transformation optics Invisibility cloaks Full-parameter Omnidirectional

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Fabrication-Constrained Conjugate Adjoint Gradient Inverse Design for Large-Scale Aperiodic Frequency Selective Surface

Fabrication-Constrained Conjugate Adjoint Gradient Inverse D...

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2023 International Applied Computational Electromagnetics Society Symposium, ACES-China 2023

作者： Zhu, Enze Li, Erji Wei, Zhun Yin, Wen-Yan Wang, Qian Innovative Institute of Electromagnetic Information and Electronic Integration Zhejiang University Key Lab of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang Province Hangzhou China Avic Research Institute for Special Structures of Aeronautical Composites Aeronautical Science Key Lab for High Performance Electromagnetic Windows Jinan China

ISBN: (纸本)9781733509657

In this paper, a fabrication-constrained conjugate adjoint gradient inverse design method (FCAG-IDM) is proposed to optimize the structural parameters of large-scale aperiodic frequency selective surfaces (FSSs). A characteristic of the proposed FCAG-IDM is that it constrains the optimized variables in each iteration considering the fabrication precision. The main advantage of FCAG-IDM is to achieve a fast inverse design for the scattering performance of electrically large-scale structure by combining fast forward simulator, conjugate adjoint gradient descent, and fabrication-constraint. The proposed FCAG-IDM is validated by both numerical and experimental results. © 2023 Applied Computational Electromagnetics Society (ACES).

关键词： Fabrication

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