1
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Li YW, Chen MN, Dai JY, Zhou Y. Guiding infrared electromagnetic waves through TI nanowires with extremely large wavenumber and azimuthal index. J Phys Condens Matter 2024; 36:275001. [PMID: 38537285 DOI: 10.1088/1361-648x/ad3876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Accepted: 03/27/2024] [Indexed: 04/09/2024]
Abstract
In this paper, the dispersion relations of the surface plasmon polaritons (SPPs) in TI nanowires have been investigated. For simplicity, TI nanowire has been modeled as a dielectric cylinder with a conductive surface, the conductivity of which is an anti-symmetric tensor. The off-diagonal terms of the conductivity tensor only slightly change the dispersion relations. Due to small conductivities, these SPPs have extremely large wavenumbers and azimuthal indices; the electric fields are tightly confined near the conductive surface. For high-order modes, cut-off phenomena have been observed. In the end, the effects of losses and much larger bulk permittivities on the dispersion relations of surface plasmons have been discussed. The simple model proposed in this paper can be directly applied to other materials with arbitrary surface conductivity. Our investigations show that TI nanostructures are promising platforms for nanophotonic applications in the future.
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Affiliation(s)
- Y W Li
- School of Science, Hangzhou Dianzi University, Hangzhou 310018, People's Republic of China
| | - M N Chen
- School of Science, Hangzhou Dianzi University, Hangzhou 310018, People's Republic of China
| | - J Y Dai
- School of Science, Hangzhou Dianzi University, Hangzhou 310018, People's Republic of China
| | - Yu Zhou
- School of Science, Hangzhou Dianzi University, Hangzhou 310018, People's Republic of China
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2
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Li G, Sun Q, Fu Y, Hou S, Zhang J, Xu KL, Dai JY. A single crystal row-column-array for 3D ultrasound imaging. Ultrasonics 2024; 139:107289. [PMID: 38492351 DOI: 10.1016/j.ultras.2024.107289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 03/03/2024] [Accepted: 03/03/2024] [Indexed: 03/18/2024]
Abstract
In vivo 3D ultrasound imaging with 2D-array transducers is of great importance for both clinical application and biomedical research, but it is complicated in fabrication and also very expensive in hardware due to thousands of electronic channels. In this work, we demonstrate a new fabrication process of 7-MHz 128 + 128 elements row-column-array (RCA) transducer with relaxor ferroelectric PMN-0.28PT single crystal. With piezoelectric single crystal and improved acoustic matching, the optimized performance of -6 dB bandwidth of ∼82 % and insertion loss of -44.6 dB is achieved. The axial and lateral imaging resolutions at different depth of the RCA transducer are quantified by the point spread function (PSF), and the results are respectively 0.20 mm and 0.41 mm at the depth of 7.7 mm, and 0.22 mm and 0.47 mm at the depth of 16.7 mm. The transducer is validated experimentally on a hyperechoic phantom, and 3D view and slices of B-mode images are obtained. The experimental results indicate that our developed RCA transducer can obtain high-quality 3D ultrasound images, demonstrating great potential on ultrafast 3D and functional imaging.
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Affiliation(s)
- Guo Li
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, China; School of Automation, Xi'an University of Posts &Telecommunications, Xi'an, China.
| | - Qiandong Sun
- Department of Biomedical Engineering, Fudan University, Shanghai, China
| | - Yapeng Fu
- Department of Biomedical Engineering, Fudan University, Shanghai, China
| | - Shilin Hou
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, China
| | - Jiaming Zhang
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, China
| | - K L Xu
- Department of Biomedical Engineering, Fudan University, Shanghai, China; Shanghai Poda Medical Technology Co., Ltd., Shanghai, China.
| | - J Y Dai
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, China.
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3
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Wang SR, Dai JY, Ke JC, Chen ZY, Zhou QY, Qi ZJ, Lu YJ, Huang Y, Sun MK, Cheng Q, Cui TJ. Radar Micro-Doppler Signature Generation Based on Time-Domain Digital Coding Metasurface. Adv Sci (Weinh) 2024:e2306850. [PMID: 38477543 DOI: 10.1002/advs.202306850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 01/27/2024] [Indexed: 03/14/2024]
Abstract
Micro-Doppler effect is a vital feature of a target that reflects its oscillatory motions apart from bulk motion and provides an important evidence for target recognition with radars. However, establishing the micro-Doppler database poses a great challenge, since plenty of experiments are required to get the micro-Doppler signatures of different targets for the purpose of analyses and interpretations with radars, which are dramatically limited by high cost and time-consuming. Aiming to overcome these limits, a low-cost and powerful simulation platform of the micro-Doppler effects is proposed based on time-domain digital coding metasurface (TDCM). Owing to the outstanding capabilities of TDCM in generating and manipulating nonlinear harmonics during wave-matter interactions, it enables to supply rich and high-precision electromagnetic signals with multiple micro-Doppler frequencies to describe the micro-motions of different objects, which are especially favored for the training of artificial intelligence algorithms in automatic target recognition and benefit a host of applications like imaging and biosensing.
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Affiliation(s)
- Si Ran Wang
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China
| | - Jun Yan Dai
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China
| | - Jun Chen Ke
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China
| | - Zhan Ye Chen
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China
| | - Qun Yan Zhou
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China
| | - Zhen Jie Qi
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China
| | - Ying Juan Lu
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China
| | - Yan Huang
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
| | - Meng Ke Sun
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China
| | - Qiang Cheng
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China
| | - Tie Jun Cui
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China
- Pazhou Laboratory, Huangpu, Guangzhou, 510555, China
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4
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Liu Y, Wang Y, Fu X, Shi L, Yang F, Luo J, Zhou QY, Fu Y, Chen Q, Dai JY, Zhang L, Cheng Q, Cui TJ. Toward Sub-Terahertz: Space-Time Coding Metasurface Transmitter for Wideband Wireless Communications. Adv Sci (Weinh) 2023; 10:e2304278. [PMID: 37552812 PMCID: PMC10582441 DOI: 10.1002/advs.202304278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 07/20/2023] [Indexed: 08/10/2023]
Abstract
A space-time coding metasurface (STCM) operating in the sub-terahertz band to construct new-architecture wireless communication systems is proposed. Specifically, a programmable STCM is designed with varactor-diode-tuned metasurface elements, enabling precise regulation of harmonic amplitudes and phases by adjusting the time delay and duty cycle of square-wave modulation signal loaded on the varactor diodes. Independent electromagnetic (EM) regulations in the space and time domains are achieved by STCM to realize flexible beam manipulations and information modulations. Based on these features, a sub-terahertz wireless communication link is constructed by employing STCM as a transmitter. Experimental results demonstrate that the STCM supports multiple modulation schemes including frequency-shift keying, phase-shift keying, and quadrature amplitude modulations in a wide frequency band. It is also shown that the STCM is capable of realizing wide-angle beam scanning in the range of ±45o , which offers an opportunity for user tracking during the communication. Thus, the STCM transmitter with high device density and low power consumption can provide low-complexity, low-cost, low-power, and low-heat solutions for building the next-generation wireless communication systems in the sub-terahertz frequency and even terahertz band.
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Affiliation(s)
- Yujie Liu
- State Key Laboratory of Millimeter WavesSoutheast UniversityNanjing210096China
| | - Yu Wang
- State Key Laboratory of Millimeter WavesSoutheast UniversityNanjing210096China
| | - Xiaojian Fu
- State Key Laboratory of Millimeter WavesSoutheast UniversityNanjing210096China
- Institute of Electromagnetic SpaceSoutheast UniversityNanjing210096China
| | - Lei Shi
- State Key Laboratory of Millimeter WavesSoutheast UniversityNanjing210096China
| | - Fei Yang
- State Key Laboratory of Millimeter WavesSoutheast UniversityNanjing210096China
| | - Jiang Luo
- School of Electronics and InformationHangzhou Dianzi UniversityHangzhou310018China
| | - Qun Yan Zhou
- State Key Laboratory of Millimeter WavesSoutheast UniversityNanjing210096China
| | - Yuan Fu
- State Key Laboratory of Millimeter WavesSoutheast UniversityNanjing210096China
| | - Qi Chen
- State Key Laboratory of Millimeter WavesSoutheast UniversityNanjing210096China
| | - Jun Yan Dai
- State Key Laboratory of Millimeter WavesSoutheast UniversityNanjing210096China
- Institute of Electromagnetic SpaceSoutheast UniversityNanjing210096China
| | - Lei Zhang
- State Key Laboratory of Millimeter WavesSoutheast UniversityNanjing210096China
- Institute of Electromagnetic SpaceSoutheast UniversityNanjing210096China
| | - Qiang Cheng
- State Key Laboratory of Millimeter WavesSoutheast UniversityNanjing210096China
- Institute of Electromagnetic SpaceSoutheast UniversityNanjing210096China
| | - Tie Jun Cui
- State Key Laboratory of Millimeter WavesSoutheast UniversityNanjing210096China
- Institute of Electromagnetic SpaceSoutheast UniversityNanjing210096China
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5
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Wang SR, Dai JY, Zhou QY, Ke JC, Cheng Q, Cui TJ. Manipulations of multi-frequency waves and signals via multi-partition asynchronous space-time-coding digital metasurface. Nat Commun 2023; 14:5377. [PMID: 37666804 PMCID: PMC10477258 DOI: 10.1038/s41467-023-41031-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 08/21/2023] [Indexed: 09/06/2023] Open
Abstract
Manipulations of multiple carrier frequencies are especially important in a variety of fields like radar detection and wireless communications. In conventional radio-frequency architecture, the multi-frequency control is implemented by microwave circuits, which are hard to integrate with antenna apertures, thus bringing the problems of expensive system and high power consumption. Previous studies demonstrate the possibility to jointly control the multiple harmonics using space-time-coding digital metasurface, but suffer from the drawback of inherent harmonic entanglement. To overcome the difficulties, we propose a multi-partition asynchronous space-time-coding digital metasurface (ASTCM) to generate and manipulate multiple frequencies with more flexibility. We further establish an ASTCM-based transmitter to realize wireless communications with frequency-division multiplexing, where the metasurface is responsible for carrier-wave generations and signal modulations. The direct multi-frequency controls with ASTCM provides a new avenue to simplify the traditional wireless systems with reduced costs and low power consumption.
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Affiliation(s)
- Si Ran Wang
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China
| | - Jun Yan Dai
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China
| | - Qun Yan Zhou
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China
| | - Jun Chen Ke
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China
| | - Qiang Cheng
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China.
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China.
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China.
| | - Tie Jun Cui
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China.
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China.
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China.
- Pazhou Laboratory, Huangpu, 510555, Guangzhou, China.
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6
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Wu GB, Dai JY, Shum KM, Chan KF, Cheng Q, Cui TJ, Chan CH. A universal metasurface antenna to manipulate all fundamental characteristics of electromagnetic waves. Nat Commun 2023; 14:5155. [PMID: 37620303 PMCID: PMC10449906 DOI: 10.1038/s41467-023-40717-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 08/01/2023] [Indexed: 08/26/2023] Open
Abstract
Metasurfaces have promising potential to revolutionize a variety of photonic and electronic device technologies. However, metasurfaces that can simultaneously and independently control all electromagnetics (EM) waves' properties, including amplitude, phase, frequency, polarization, and momentum, with high integrability and programmability, are challenging and have not been successfully attempted. Here, we propose and demonstrate a microwave universal metasurface antenna (UMA) capable of dynamically, simultaneously, independently, and precisely manipulating all the constitutive properties of EM waves in a software-defined manner. Our UMA further facilitates the spatial- and time-varying wave properties, leading to more complicated waveform generation, beamforming, and direct information manipulations. In particular, the UMA can directly generate the modulated waveforms carrying digital information that can fundamentally simplify the architecture of information transmitter systems. The proposed UMA with unparalleled EM wave and information manipulation capabilities will spark a surge of applications from next-generation wireless systems, cognitive sensing, and imaging to quantum optics and quantum information science.
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Affiliation(s)
- Geng-Bo Wu
- State Key Laboratory of Terahertz and Millimeter Waves, City University of Hong Kong, Hong Kong, 999077, China
- Department of Electrical Engineering, City University of Hong Kong, Hong Kong, 999077, China
| | - Jun Yan Dai
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China.
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China.
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China.
| | - Kam Man Shum
- State Key Laboratory of Terahertz and Millimeter Waves, City University of Hong Kong, Hong Kong, 999077, China
| | - Ka Fai Chan
- State Key Laboratory of Terahertz and Millimeter Waves, City University of Hong Kong, Hong Kong, 999077, China
| | - Qiang Cheng
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China.
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China.
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China.
| | - Tie Jun Cui
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China.
- Institute of Electromagnetic Space, Southeast University, Nanjing, 210096, China.
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing, 210096, China.
| | - Chi Hou Chan
- State Key Laboratory of Terahertz and Millimeter Waves, City University of Hong Kong, Hong Kong, 999077, China.
- Department of Electrical Engineering, City University of Hong Kong, Hong Kong, 999077, China.
- Guangdong-Hong Kong Joint Laboratory for Big Data Imaging and Communication, Shenzhen, 518048, China.
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7
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Wong CM, Chan SF, Liu R, Zhang J, Wu WC, Liang Z, Yau HM, Wang DY, Li S, Lam KH, Qiu WB, Luo HS, Dai JY. 20-MHz phased array ultrasound transducer for in vivo ultrasound imaging of small animals. Ultrasonics 2022; 126:106821. [PMID: 35988512 DOI: 10.1016/j.ultras.2022.106821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 07/16/2022] [Accepted: 08/04/2022] [Indexed: 06/15/2023]
Abstract
In vivo ultrasound imaging with phased array transducers is of great importance for both clinical application and biomedical research. In this work, relaxor ferroelectric PMN-0.28PT single crystal with very high piezoelectric constant d33 ≥ 2000 pC/N and electromechanical coupling coefficient k33 ∼ 0.92 is used to fabricate high-frequency phased array transducers. A 128-element 20-MHz phased array transducer is successfully fabricated, and the optimized performance of -6 dB average bandwidth of ∼ 84 % and insertion loss of -43 dB are achieved. The axial and lateral imaging resolutions of the transducer are determined to be 81 µm and 243 µm, respectively. With Verasonics image platform, in vivo fisheye images are acquired, demonstrating the potential application of our developed high-frequency phased array transducer for biomedical research on small animals.
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Affiliation(s)
- C M Wong
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, China; Hospital Authority, Hong Kong, China
| | - S F Chan
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, China
| | - R Liu
- Shenzhen Key Laboratory of Ultrasound Imaging and Therapy, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - J Zhang
- Department of Electrical Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - W C Wu
- Shenzhen Key Laboratory of Ultrasound Imaging and Therapy, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China; School of Materials Science and Engineering, The University of New South Wales (UNSW Sydney), Australia
| | - Z Liang
- Shanghai Institute of Ceramics, The Chinese Academy of Sciences, Shanghai, China
| | - H M Yau
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, China; Hospital Authority, Hong Kong, China
| | - D Y Wang
- School of Materials Science and Engineering, The University of New South Wales (UNSW Sydney), Australia
| | - S Li
- School of Materials Science and Engineering, The University of New South Wales (UNSW Sydney), Australia
| | - K H Lam
- Department of Electrical Engineering, The Hong Kong Polytechnic University, Hong Kong, China.
| | - W B Qiu
- Shenzhen Key Laboratory of Ultrasound Imaging and Therapy, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.
| | - H S Luo
- Shanghai Institute of Ceramics, The Chinese Academy of Sciences, Shanghai, China
| | - J Y Dai
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, China.
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8
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Ke JC, Chen X, Tang W, Chen MZ, Zhang L, Wang L, Dai JY, Yang J, Zhang JW, Wu L, Cheng Q, Jin S, Cui TJ. Space-frequency-polarization-division multiplexed wireless communication system using anisotropic space-time-coding digital metasurface. Natl Sci Rev 2022; 9:nwac225. [PMID: 36452428 PMCID: PMC9701098 DOI: 10.1093/nsr/nwac225] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Revised: 08/21/2022] [Accepted: 10/01/2022] [Indexed: 08/26/2023] Open
Abstract
In the past few years, wireless communications based on digital coding metasurfaces have gained research interest owing to their simplified architectures and low cost. However, in most of the metasurface-based wireless systems, a single-polarization scenario is used, limiting the channel capacities. To solve the problem, multiplexing methods have been adopted, but the system complexity is inevitably increased. Here, a space-frequency-polarization-division multiplexed wireless communication system is proposed using an anisotropic space-time-coding digital metasurface. By separately designing time-varying control voltage sequences for differently oriented varactor diodes integrated on the metasurface, we achieve frequency-polarization-division multiplexed modulations. By further introducing different time-delay gradients to the control voltage sequences in two polarization directions, we successfully obtain space-frequency-polarization-division multiplexed modulations to realize a wireless communication system with a new architecture. The new communication system is designed with compact dual-polarized meta-elements, and can improve channel capacity and space utilization. Experimental results demonstrate the high-performance and real-time transmission capability of the proposed communication system, confirming its potential application in multiple-user collaborative wireless communications.
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Affiliation(s)
- Jun Chen Ke
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing210096, China
- Institute of Electromagnetic Space, Southeast University, Nanjing210096,China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing210096, China
| | - Xiangyu Chen
- National Mobile Communications Research Laboratory, Southeast University, Nanjing210096, China
| | - Wankai Tang
- National Mobile Communications Research Laboratory, Southeast University, Nanjing210096, China
| | - Ming Zheng Chen
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing210096, China
- Institute of Electromagnetic Space, Southeast University, Nanjing210096,China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing210096, China
| | - Lei Zhang
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing210096, China
- Institute of Electromagnetic Space, Southeast University, Nanjing210096,China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing210096, China
| | - Li Wang
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing210096, China
- Institute of Electromagnetic Space, Southeast University, Nanjing210096,China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing210096, China
| | - Jun Yan Dai
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing210096, China
- Institute of Electromagnetic Space, Southeast University, Nanjing210096,China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing210096, China
| | - Jin Yang
- SoutheastUniversity Wuxi Campus, Wuxi214061, China
| | - Jun Wei Zhang
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing210096, China
- Institute of Electromagnetic Space, Southeast University, Nanjing210096,China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing210096, China
| | - Lijie Wu
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing210096, China
- Institute of Electromagnetic Space, Southeast University, Nanjing210096,China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing210096, China
| | - Qiang Cheng
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing210096, China
- Institute of Electromagnetic Space, Southeast University, Nanjing210096,China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing210096, China
| | - Shi Jin
- National Mobile Communications Research Laboratory, Southeast University, Nanjing210096, China
| | - Tie Jun Cui
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing210096, China
- Institute of Electromagnetic Space, Southeast University, Nanjing210096,China
- Frontiers Science Center for Mobile Information Communication and Security, Southeast University, Nanjing210096, China
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9
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Ke JC, Dai JY, Zhang JW, Chen Z, Chen MZ, Lu Y, Zhang L, Wang L, Zhou QY, Li L, Ding JS, Cheng Q, Cui TJ. Frequency-modulated continuous waves controlled by space-time-coding metasurface with nonlinearly periodic phases. Light Sci Appl 2022; 11:273. [PMID: 36104318 PMCID: PMC9474547 DOI: 10.1038/s41377-022-00973-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 08/28/2022] [Accepted: 08/28/2022] [Indexed: 05/25/2023]
Abstract
The rapid development of space-time-coding metasurfaces (STCMs) offers a new avenue to manipulate spatial electromagnetic beams, waveforms, and frequency spectra simultaneously with high efficiency. To date, most studies are primarily focused on harmonic generations and independent controls of finite-order harmonics and their spatial waves, but the manipulations of continuously temporal waveforms that include much rich frequency spectral components are still limited in both theory and experiment based on STCM. Here, we propose a theoretical framework and method to generate frequency-modulated continuous waves (FMCWs) and control their spatial propagation behaviors simultaneously via a novel STCM with nonlinearly periodic phases. Since the carrier frequency of FMCW changes with time rapidly, we can produce customized time-varying reflection phases at will by the required FMCW under the illumination of a monochromatic wave. More importantly, the propagation directions of the time-varying beams can be controlled by encoding the metasurface with different initial phase gradients. A programmable STCM prototype with a full-phase range is designed and fabricated to realize reprogrammable FMCW functions, and experimental results show good agreement with the theoretical analyses.
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Affiliation(s)
- Jun Chen Ke
- Institute of Electromagnetic Space, Southeast University, 210096, Nanjing, China
- State Key Laboratory of Millimeter Waves, Southeast University, 210096, Nanjing, China
| | - Jun Yan Dai
- Institute of Electromagnetic Space, Southeast University, 210096, Nanjing, China
- State Key Laboratory of Millimeter Waves, Southeast University, 210096, Nanjing, China
| | - Jun Wei Zhang
- Institute of Electromagnetic Space, Southeast University, 210096, Nanjing, China
- State Key Laboratory of Millimeter Waves, Southeast University, 210096, Nanjing, China
| | - Zhanye Chen
- Institute of Electromagnetic Space, Southeast University, 210096, Nanjing, China
- State Key Laboratory of Millimeter Waves, Southeast University, 210096, Nanjing, China
| | - Ming Zheng Chen
- Institute of Electromagnetic Space, Southeast University, 210096, Nanjing, China
- State Key Laboratory of Millimeter Waves, Southeast University, 210096, Nanjing, China
| | - Yunfeng Lu
- Institute of Electromagnetic Space, Southeast University, 210096, Nanjing, China
- State Key Laboratory of Millimeter Waves, Southeast University, 210096, Nanjing, China
| | - Lei Zhang
- Institute of Electromagnetic Space, Southeast University, 210096, Nanjing, China
- State Key Laboratory of Millimeter Waves, Southeast University, 210096, Nanjing, China
| | - Li Wang
- Institute of Electromagnetic Space, Southeast University, 210096, Nanjing, China
- State Key Laboratory of Millimeter Waves, Southeast University, 210096, Nanjing, China
| | - Qun Yan Zhou
- Institute of Electromagnetic Space, Southeast University, 210096, Nanjing, China
- State Key Laboratory of Millimeter Waves, Southeast University, 210096, Nanjing, China
| | - Long Li
- School of Electronic Engineering, Xidian University, 710071, Xi'an, China
| | - Jin Shan Ding
- School of Electronic Engineering, Xidian University, 710071, Xi'an, China
| | - Qiang Cheng
- Institute of Electromagnetic Space, Southeast University, 210096, Nanjing, China.
- State Key Laboratory of Millimeter Waves, Southeast University, 210096, Nanjing, China.
| | - Tie Jun Cui
- Institute of Electromagnetic Space, Southeast University, 210096, Nanjing, China.
- State Key Laboratory of Millimeter Waves, Southeast University, 210096, Nanjing, China.
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10
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Wei C, Zheng KY, Dai JY, Cai HC, Zhu TN, Zhao JL, Zhou DB, Zhuang JL. [The 492nd case: recurrent thrombosis, thrombocytopenia]. Zhonghua Nei Ke Za Zhi 2022; 61:239-242. [PMID: 35090264 DOI: 10.3760/cma.j.cn112138-20210222-00149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A 43-year-old female patient was admitted with recurrent thrombosis for more than 2 years and thrombocytopenia for more than 1 year. Both arterial and venous thromboses developed especially at rare sites even during anticoagulation therapy such as cerebral venous sinus thrombosis. Antinuclear antibody, anti-ENA antibody and antiphospholipid antibody were all negative. Platelet count elevated to normal after high dose glucocorticoid and intravenous immunoglobulin (IVIG). Immune thrombocytopenia was suspected. When 4 grade thrombocytopenia recurred, intravenous heparin, rituximab 600 mg, IVIG and eltrombopag were administrated. After 3 weeks, thrombocytopenia did not improve, and new thrombosis developed instead. Screening of thrombophilia related genes revealed PROS1 gene heterozygous mutation and MTHFR TT genotype. Low amount of serum IgG κ monoclonal protein was detected. Heparin-induced thrombocytopenia was differentiated and excluded. Finally, serum negative antiphospholipid syndrome was considered the most likely diagnosis. Dexamethasone 20 mg/day × 4 days combined with sirolimus 2 mg/day was prescribed. The patient was discharged with low molecular weight heparin. At one month, her headache was greatly relieved. The platelet count raised to 20-30×109/L, and no new thrombosis or bleeding was reported.
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Affiliation(s)
- C Wei
- Department of Hematology, Peking Union Medical College Hospital,Peking Union Medical College, Chinese Academy of Medical Sciences,Beijing 100730,China
| | - K Y Zheng
- Department of Internal Medicine, Peking Union Medical College Hospital,Peking Union Medical College, Chinese Academy of Medical Sciences,Beijing 100730, China
| | - J Y Dai
- Department of Emergency, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences,Beijing 100730,China
| | - H C Cai
- Department of Hematology, Peking Union Medical College Hospital,Peking Union Medical College, Chinese Academy of Medical Sciences,Beijing 100730,China
| | - T N Zhu
- Department of Hematology, Peking Union Medical College Hospital,Peking Union Medical College, Chinese Academy of Medical Sciences,Beijing 100730,China
| | - J L Zhao
- Department of Rheumatology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - D B Zhou
- Department of Hematology, Peking Union Medical College Hospital,Peking Union Medical College, Chinese Academy of Medical Sciences,Beijing 100730,China
| | - J L Zhuang
- Department of Hematology, Peking Union Medical College Hospital,Peking Union Medical College, Chinese Academy of Medical Sciences,Beijing 100730,China
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11
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Chen MZ, Tang W, Dai JY, Ke JC, Zhang L, Zhang C, Yang J, Li L, Cheng Q, Jin S, Cui TJ. Accurate and broadband manipulations of harmonic amplitudes and phases to reach 256 QAM millimeter-wave wireless communications by time-domain digital coding metasurface. Natl Sci Rev 2021; 9:nwab134. [PMID: 35079409 PMCID: PMC8783670 DOI: 10.1093/nsr/nwab134] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 06/22/2021] [Accepted: 07/20/2021] [Indexed: 12/31/2022] Open
Abstract
We propose a theoretical mechanism and new coding strategy to realize extremely accurate manipulations of nonlinear electromagnetic harmonics in ultrawide frequency band based on a time-domain digital coding metasurface (TDCM). Using the proposed mechanism and coding strategy, we design and fabricate a millimeter-wave (mmWave) TDCM, which is composed of reprogrammable meta-atoms embedded with positive-intrinsic-negative diodes. By controlling the duty ratios and time delays of the digital coding sequences loaded on a TDCM, experimental results show that both amplitudes and phases of different harmonics can be engineered at will simultaneously and precisely in broad frequency band from 22 to 33 GHz, even when the coding states are imperfect, which is in good agreement with theoretical calculations. Based on the fabricated high-performance TDCM, we further propose and experimentally realize a large-capacity mmWave wireless communication system, where 256 quadrature amplitude modulation, along with other schemes, is demonstrated. The new wireless communication system has a much simpler architecture than the currently used mmWave wireless systems, and hence can significantly reduce the hardware cost. We believe that the proposed method and system architecture can find vast application in future mmWave and terahertz-wave wireless communication and radar systems.
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Affiliation(s)
- Ming Zheng Chen
- Institute of Electromagnetic Space, Southeast University, Nanjing 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
- Center of Intelligent Metamaterials, Pazhou Laboratory, Guangzhou 510330, China
| | - Wankai Tang
- National Mobile Communications Research Laboratory, Southeast University, Nanjing 210096, China
- Center of Intelligent Metamaterials, Pazhou Laboratory, Guangzhou 510330, China
| | - Jun Yan Dai
- Institute of Electromagnetic Space, Southeast University, Nanjing 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
- State Key Laboratory of Terahertz and Millimeter Waves, City University of Hong Kong, Hong Kong, China
| | - Jun Chen Ke
- Institute of Electromagnetic Space, Southeast University, Nanjing 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
| | - Lei Zhang
- Institute of Electromagnetic Space, Southeast University, Nanjing 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
- Center of Intelligent Metamaterials, Pazhou Laboratory, Guangzhou 510330, China
| | - Cheng Zhang
- Institute of Electromagnetic Space, Southeast University, Nanjing 210096, China
| | - Jin Yang
- Institute of Electromagnetic Space, Southeast University, Nanjing 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
- Center of Intelligent Metamaterials, Pazhou Laboratory, Guangzhou 510330, China
| | - Lianlin Li
- State Key Laboratory of Advanced Optical Communication Systems and Networks, Department of Electronics, Peking University, Beijing 100871, China
- Center of Intelligent Metamaterials, Pazhou Laboratory, Guangzhou 510330, China
| | - Qiang Cheng
- Institute of Electromagnetic Space, Southeast University, Nanjing 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
- Center of Intelligent Metamaterials, Pazhou Laboratory, Guangzhou 510330, China
| | - Shi Jin
- Institute of Electromagnetic Space, Southeast University, Nanjing 210096, China
- National Mobile Communications Research Laboratory, Southeast University, Nanjing 210096, China
- Center of Intelligent Metamaterials, Pazhou Laboratory, Guangzhou 510330, China
| | - Tie Jun Cui
- Institute of Electromagnetic Space, Southeast University, Nanjing 210096, China
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
- Center of Intelligent Metamaterials, Pazhou Laboratory, Guangzhou 510330, China
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12
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Zhang L, Chen XQ, Shao RW, Dai JY, Cheng Q, Castaldi G, Galdi V, Cui TJ. Breaking Reciprocity with Space-Time-Coding Digital Metasurfaces. Adv Mater 2019; 31:e1904069. [PMID: 31420926 DOI: 10.1002/adma.201904069] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 07/29/2019] [Indexed: 05/14/2023]
Abstract
Metasurfaces are artificially engineered ultrathin structures that can finely tailor and control electromagnetic wavefronts. There is currently a strong interest in exploring their capability to lift some fundamental limitations dictated by Lorentz reciprocity, which have strong implications in communication, heat management, and energy harvesting. Time-varying approaches have emerged as attractive alternatives to conventional schemes relying on magnetic or nonlinear materials, but experimental evidence is currently limited to devices such as circulators and antennas. Here, the recently proposed concept of space-time-coding digital metasurfaces is leveraged to break reciprocity. Moreover, it is shown that such nonreciprocal effects can be controlled dynamically. This approach relies on inducing suitable spatiotemporal phase gradients in a programmable way via digital modulation of the metasurface-elements' phase repsonse, which enable anomalous reflections accompanied by frequency conversions. A prototype operating at microwave frequencies is designed and fabricated for proof-of-concept validation. Measured results are in good agreement with theory, hence providing the first experimental evidence of nonreciprocal reflection effects enabled by space-time-modulated digital metasurfaces. The proposed concept and platform set the stage for "on-demand" realization of nonreciprocal effects, in programmable or reconfigurable fashions, which may find several promising applications, including frequency conversion, Doppler frequency illusion, optical isolation, and unidirectional transmission.
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Affiliation(s)
- Lei Zhang
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
| | - Xiao Qing Chen
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
| | - Rui Wen Shao
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
| | - Jun Yan Dai
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
| | - Qiang Cheng
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
| | - Giuseppe Castaldi
- Fields & Waves Lab, Department of Engineering, University of Sannio, I-82100, Benevento, Italy
| | - Vincenzo Galdi
- Fields & Waves Lab, Department of Engineering, University of Sannio, I-82100, Benevento, Italy
| | - Tie Jun Cui
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing, 210096, China
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13
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Zhao J, Yang X, Dai JY, Cheng Q, Li X, Qi NH, Ke JC, Bai GD, Liu S, Jin S, Alù A, Cui TJ. Programmable time-domain digital-coding metasurface for non-linear harmonic manipulation and new wireless communication systems. Natl Sci Rev 2018; 6:231-238. [PMID: 34691861 PMCID: PMC8291514 DOI: 10.1093/nsr/nwy135] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 10/25/2018] [Accepted: 11/13/2018] [Indexed: 12/03/2022] Open
Abstract
Optical non-linear phenomena are typically observed in natural materials interacting with light at high intensities, and they benefit a diverse range of applications from communication to sensing. However, controlling harmonic conversion with high efficiency and flexibility remains a major issue in modern optical and radio-frequency systems. Here, we introduce a dynamic time-domain digital-coding metasurface that enables efficient manipulation of spectral harmonic distribution. By dynamically modulating the local phase of the surface reflectivity, we achieve accurate control of different harmonics in a highly programmable and dynamic fashion, enabling unusual responses, such as velocity illusion. As a relevant application, we propose and realize a novel architecture for wireless communication systems based on the time-domain digital-coding metasurface, which largely simplifies the architecture of modern communication systems, at the same time yielding excellent performance for real-time signal transmission. The presented work, from new concept to new system, opens new pathways in the application of metamaterials to practical technology.
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Affiliation(s)
- Jie Zhao
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
| | - Xi Yang
- National Mobile Communication Research Laboratory, Southeast University, Nanjing 210096, China
| | - Jun Yan Dai
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
| | - Qiang Cheng
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
- Synergetic Innovation Center of Wireless Communication Technology, Southeast University, Nanjing 210096, China
| | - Xiang Li
- National Mobile Communication Research Laboratory, Southeast University, Nanjing 210096, China
| | - Ning Hua Qi
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
| | - Jun Chen Ke
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
| | - Guo Dong Bai
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
| | - Shuo Liu
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
| | - Shi Jin
- National Mobile Communication Research Laboratory, Southeast University, Nanjing 210096, China
- Synergetic Innovation Center of Wireless Communication Technology, Southeast University, Nanjing 210096, China
| | - Andrea Alù
- Photonics Initiative, Advanced Science Research Center, City University of New York, New York, NY 10031, USA
- Physics Program, The Graduate Center, City University of New York, New York, NY 10016, USA
- Department of Electrical Engineering, City College of New York, New York, NY 10031, USA
| | - Tie Jun Cui
- State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
- Synergetic Innovation Center of Wireless Communication Technology, Southeast University, Nanjing 210096, China
- Jiangsu Cyber-Space Science & Technology Co., Ltd, Nanjing 211111, China
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14
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Dai JY, Zhao J, Cheng Q, Cui TJ. Independent control of harmonic amplitudes and phases via a time-domain digital coding metasurface. Light Sci Appl 2018; 7:90. [PMID: 30479756 PMCID: PMC6249241 DOI: 10.1038/s41377-018-0092-z] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 10/23/2018] [Accepted: 11/03/2018] [Indexed: 05/06/2023]
Abstract
Harmonic manipulations are important for applications such as wireless communications, radar detection and biological monitoring. A general approach to tailor the harmonics involves the use of additional amplifiers and phase shifters for the precise control of harmonic amplitudes and phases after the mixing process; however, this approach leads to issues of high cost and system integration. Metasurfaces composed of a periodic array of subwavelength resonators provide additional degrees of freedom to realize customized responses to incident light and highlight the possibility for nonlinear control by taking advantage of time-domain properties. Here, we designed and experimentally characterized a reflective time-domain digital coding metasurface, with independent control of the harmonic amplitude and phase. As the reflection coefficient is dynamically modulated in a predefined way, a large conversion rate is observed from the carrier signal to the harmonic components, with magnitudes and phases that can be accurately and separately engineered. In addition, by encoding the reflection phases of the meta-atoms, beam scanning for multiple harmonics can be implemented via different digital coding sequences, thus removing the need for intricate phase-shift networks. This work paves the way for efficient harmonic control for applications in communications, radar, and related areas.
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Affiliation(s)
- Jun Yan Dai
- State Key Laboratory of Millimeter Waves, Southeast University, 210096 Nanjing, China
- Synergetic Innovation Center of Wireless Communication Technology, Southeast University, 210096 Nanjing, China
| | - Jie Zhao
- State Key Laboratory of Millimeter Waves, Southeast University, 210096 Nanjing, China
- Synergetic Innovation Center of Wireless Communication Technology, Southeast University, 210096 Nanjing, China
| | - Qiang Cheng
- State Key Laboratory of Millimeter Waves, Southeast University, 210096 Nanjing, China
- Synergetic Innovation Center of Wireless Communication Technology, Southeast University, 210096 Nanjing, China
| | - Tie Jun Cui
- State Key Laboratory of Millimeter Waves, Southeast University, 210096 Nanjing, China
- Synergetic Innovation Center of Wireless Communication Technology, Southeast University, 210096 Nanjing, China
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15
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Fang HJ, Chen Y, Wong CM, Qiu WB, Chan HLW, Dai JY, Li Q, Yan QF. Anodic aluminum oxide-epoxy composite acoustic matching layers for ultrasonic transducer application. Ultrasonics 2016; 70:29-33. [PMID: 27125558 DOI: 10.1016/j.ultras.2016.04.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 03/31/2016] [Accepted: 04/03/2016] [Indexed: 06/05/2023]
Abstract
The goal of this work is to demonstrate the application of anodic aluminum oxide (AAO) template as matching layer of ultrasonic transducer. Quarter-wavelength acoustic matching layer is known as a vital component in medical ultrasonic transducers to compensate the acoustic impedance mismatch between piezoelectric element and human body. The AAO matching layer is made of anodic aluminum oxide template filled with epoxy resin, i.e. AAO-epoxy 1-3 composite. Using this composite as the first matching layer, a ∼12MHz ultrasonic transducer based on soft lead zirconate titanate piezoelectric ceramic is fabricated, and pulse-echo measurements show that the transducer exhibits very good performance with broad bandwidth of 68% (-6dB) and two-way insertion loss of -22.7dB. Wire phantom ultrasonic image is also used to evaluate the transducer's performance, and the results confirm the process feasibility and merit of AAO-epoxy composite as a new matching material for ultrasonic transducer application. This matching scheme provides a solution to address the problems existing in the conventional 0-3 composite matching layer and suggests another useful application of AAO template.
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Affiliation(s)
- H J Fang
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China; Department of Chemistry, Tsinghua University, Beijing, PR China
| | - Y Chen
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China; The Hong Kong Polytechnic University, Shenzhen Research Institute, PR China
| | - C M Wong
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China; Department of Electrical Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China
| | - W B Qiu
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - H L W Chan
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China
| | - J Y Dai
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China; The Hong Kong Polytechnic University, Shenzhen Research Institute, PR China.
| | - Q Li
- Department of Chemistry, Tsinghua University, Beijing, PR China
| | - Q F Yan
- Department of Chemistry, Tsinghua University, Beijing, PR China
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16
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Yau HM, Yan ZB, Chan NY, Au K, Wong CM, Leung CW, Zhang FY, Gao XS, Dai JY. Low-field Switching Four-state Nonvolatile Memory Based on Multiferroic Tunnel Junctions. Sci Rep 2015; 5:12826. [PMID: 26239505 PMCID: PMC4523833 DOI: 10.1038/srep12826] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 05/20/2015] [Indexed: 11/26/2022] Open
Abstract
Multiferroic tunneling junction based four-state non-volatile memories are very promising for future memory industry since this kind of memories hold the advantages of not only the higher density by scaling down memory cell but also the function of magnetically written and electrically reading. In this work, we demonstrate a success of this four-state memory in a material system of NiFe/BaTiO3/La0.7Sr0.3MnO3 with improved memory characteristics such as lower switching field and larger tunneling magnetoresistance (TMR). Ferroelectric switching induced resistive change memory with OFF/ON ratio of 16 and 0.3% TMR effect have been achieved in this multiferroic tunneling structure.
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Affiliation(s)
- H M Yau
- Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P. R. China
| | - Z B Yan
- Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China
| | - N Y Chan
- Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P. R. China
| | - K Au
- Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P. R. China
| | - C M Wong
- Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P. R. China
| | - C W Leung
- Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P. R. China
| | - F Y Zhang
- Institute for Advanced Materials and Laboratory of Quantum Engineering and Quantum Materials, South China Normal University, Guangzhou 510006, China
| | - X S Gao
- Institute for Advanced Materials and Laboratory of Quantum Engineering and Quantum Materials, South China Normal University, Guangzhou 510006, China
| | - J Y Dai
- Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P. R. China
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17
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Chen Y, Qiu WB, Lam KH, Liu BQ, Jiang XP, Zheng HR, Luo HS, Chan HLW, Dai JY. Focused intravascular ultrasonic probe using dimpled transducer elements. Ultrasonics 2015; 56:227-231. [PMID: 25108608 DOI: 10.1016/j.ultras.2014.07.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 07/09/2014] [Accepted: 07/19/2014] [Indexed: 06/03/2023]
Abstract
High-frequency focused intravascular ultrasonic probes were fabricated in this study using dimple technique based on PMN-PT single crystal and lead-free KNN-KBT-Mn ceramic. The center frequency, bandwidth, and insertion loss of the PMN-PT transducer were 34 MHz, 75%, and 22.9 dB, respectively. For the lead-free probe, the center frequency, bandwidth, and insertion loss were found to be 40 MHz, 72%, and 28.8 dB, respectively. The ultrasonic images of wire phantom and vessels with good resolution were obtained to evaluate the transducer performance. The -6 dB axial and lateral resolutions of the PMN-PT probe were determined to be 58 μm and 131 μm, respectively. For the lead-free probe, the axial and lateral resolutions were found to be 44 μm and 125 μm, respectively. These results suggest that the mechanical dimpling technique has good potential in preparing focused transducers for intravascular ultrasound applications.
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Affiliation(s)
- Y Chen
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China; Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, China
| | - W B Qiu
- Paul C. Lauterbur Research Center for Biomedical Imaging, Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - K H Lam
- Department of Electrical Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - B Q Liu
- Paul C. Lauterbur Research Center for Biomedical Imaging, Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - X P Jiang
- Department of Materials Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen, China
| | - H R Zheng
- Paul C. Lauterbur Research Center for Biomedical Imaging, Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - H S Luo
- Information Materials and Devices Research Center, Shanghai Institute of Ceramics, Chinese Academy of Science, Shanghai, China
| | - H L W Chan
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China; Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, China
| | - J Y Dai
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China; Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, China.
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18
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Chen Y, Lam KH, Zhou D, Cheng WF, Dai JY, Luo HS, Chan HLW. High frequency PMN-PT single crystal focusing transducer fabricated by a mechanical dimpling technique. Ultrasonics 2013; 53:345-349. [PMID: 22944074 DOI: 10.1016/j.ultras.2012.06.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Revised: 02/04/2012] [Accepted: 06/27/2012] [Indexed: 06/01/2023]
Abstract
High frequency (∼30MHz and ∼80MHz) focusing ultrasound transducers were fabricated using a PMN-0.28PT single crystal by a mechanical dimpling technique. The dimpled single crystal was used as an active element for the focusing transducer. Compared with a plane transducer, the focusing transducer fabricated with a dimpled active element exhibits much broader bandwidth and higher sensitivity. Besides, a high quality image can be obtained by the 30MHz focusing transducer, in which the -6dB axial and lateral resolution is 27μm and 139μm, respectively. These results prove that the dimpling technique is capable to fabricate the high frequency focusing transducers with excellent performance for imaging applications.
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Affiliation(s)
- Y Chen
- Department of Applied Physics and Materials Research Centre, The Hong Kong Polytechnic University, Hunghom, Hong Kong, China.
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19
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Au K, Li DF, Chan NY, Dai JY. Polar liquid molecule induced transport property modulation at LaAlO₃/SrTiO₃ heterointerface. Adv Mater 2012; 24:2598-2602. [PMID: 22495936 DOI: 10.1002/adma.201200673] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Indexed: 05/31/2023]
Affiliation(s)
- K Au
- Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P. R. China
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20
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Chen L, Zhang GL, Jin DZ, Yang L, Dai JY. Influence of discharge gap on the discharge stability in a short vacuum arc ion source. Rev Sci Instrum 2012; 83:02A509. [PMID: 22380205 DOI: 10.1063/1.3673008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The influence of the discharge gap between cathode and anode on the discharge stability in a short vacuum arc (SVA) ion source is presented in this paper. Planar cathode and cylindrical hollow anode made of titanium are investigated. There is a great need in present accelerator injection research for SVA source to produce the small deviation of the ion current beam. Current research shows that increasing the short discharge gap can reduce the level of ion current deviation and ion charge deviation from 29% and 31% to 15% and 17%, respectively. A microplasma plume generation mechanism in SVA and scanning electron microscopic results can be used to explain this interesting phenomenon.
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Affiliation(s)
- L Chen
- Institute of Electronic Engineering, China Academy of Engineering Physics, Mianyang, Sichuan 621900, China.
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Lam KH, Chen Y, Cheung KF, Dai JY. PMN-PT single crystal focusing transducer fabricated using a mechanical dimpling technique. Ultrasonics 2012; 52:20-4. [PMID: 21705037 DOI: 10.1016/j.ultras.2011.06.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Revised: 04/29/2011] [Accepted: 06/07/2011] [Indexed: 05/20/2023]
Abstract
A ∼5MHz focusing PMN-PT single crystal ultrasound transducer has been fabricated utilizing a mechanical dimpling technique, where the dimpled crystal wafer was used as an active element of the focusing transducer. For the dimpled focusing transducer, the effective electromechanical coupling coefficient was enhanced significantly from 0.42 to 0.56. The dimpled transducer also yields a -6dB bandwidth of 63.5% which is almost double the bandwidth of the plane transducer. An insertion loss of the dimpled transducer (-18.1dB) is much lower than that of the plane transducer. Finite element simulation also reveals specific focused beam from concave crystal surface. These promising results show that the dimpling technique can be used to develop high-resolution focusing single crystal transducers.
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Affiliation(s)
- K H Lam
- Department of Applied Physics, The Hong Kong Polytechnic University, Hunghom, Hong Kong, PR China.
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22
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Huang W, Zeng HZ, Zhu J, Hao JH, Dai JY. Effect of strain on ferroelectric and magnetic behavior in Pb(Zr0.52Ti0.48)O3-based magnetoelectric heterostructures. J Nanosci Nanotechnol 2011; 11:11227-11230. [PMID: 22409090 DOI: 10.1166/jnn.2011.4001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this paper, the "sandwich" structured magnetoelectric composite films of Pb(Zr0.52Ti0.48)O3/ NiFe2O4/Pb(Zr0.52Ti0.48)O3 and Pb(Zr0.52Ti0.48)O3/CoFe2O4/Pb(Zr0.52Ti0.48)O3 are epitaxially grown on SrRuO3/SrTiO3 substrates by pulsed-laser deposition. The crystalline quality and microstructures of these heterostructures are investigated by X-ray diffraction technique. The effects of strain on the ferroelectric, magnetic and magnetoelectric coupling properties of these thin films are systematically studied. The results show that the strain effect induced by lattice mismatch between the ferroelectric/ferromagnetic layers plays an important role in the ferroelectric and magnetic properties of these composite films. Compared to the strained Pb(Zr0.52Ti0.48)O3/ CoFe2O4/Pb(Zr0.52Ti0.48)O3 heterostructure, improved ferroelectric properties with an out-of-plane polarization (2P(r)) of 34.2 microC/cm2 and electric coercivity field of 158 kV/cm are obtained in the strain-free Pb(Zr0.52Ti0.48)O3/NiFe2O4/Pb(Zr0.52Ti0.48)O3 heterostructure. The ME measurement results not only show that the strain induced by lattice mismatch has great influence on the ME behavior, but also provide an understanding of the multilayers with full control over the interface structure at the atomic-scale.
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Affiliation(s)
- W Huang
- State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronics Science and Technology of China, Chengdu 610054, China
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23
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Abstract
The memory effects of gold (Au) nanocrystal (NC) non-volatile memory structures consisting of polyvinylpyrrolidone (PVP) K-30 polymer tunneling and control layers are investigated. The trilayer structure (PV P/Au-NCs + PV P/PV P) on p-type Si substrate was fabricated by spin coating, and transmission electron microscopy study reveals that the average size of the Au-NCs formed is about 5 nm in diameter. Capacitance-voltage (C-V) measurement on the memory structure shows a counter-clockwise hysteresis loop with a significant flat band voltage shift, revealing a memory effect of the Au-NCs with a charge density of up to 1 x 10(12) cm(-2) and a flat band voltage shift of 2.0 V. A unique feature of the double loop in the C-V curves suggests double barriers during electron tunneling. The I-V hysteresis is also characterized, and a switching mechanism of resistive change is discussed.
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Affiliation(s)
- P F Lee
- Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, People's Republic of China
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24
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Lau ST, Li H, Wong KS, Zhou QF, Zhou D, Li YC, Luo HS, Shung KK, Dai JY. Multiple matching scheme for broadband 0.72Pb(Mg(13)Nb(23))O(3)-0.28PbTiO(3) single crystal phased-array transducer. J Appl Phys 2009; 105:94908. [PMID: 19657405 PMCID: PMC2719468 DOI: 10.1063/1.3065476] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2008] [Accepted: 11/25/2008] [Indexed: 05/18/2023]
Abstract
Lead magnesium niobate-lead titanate single crystal 0.72Pb(Mg(13)Nb(23))O(3)-0.28PbTiO(3) (abbreviated as PMN-PT) was used to fabricate high performance ultrasonic phased-array transducer as it exhibited excellent piezoelectric properties. In this paper, we focus on the design and fabrication of a low-loss and wide-band transducer for medical imaging applications. A KLM model based simulation software PiezoCAD was used for acoustic design of the transducer including the front-face matching and backing. The calculated results show that the -6 dB transducer bandwidth can be improved significantly by using double lambda8 matching layers and hard backing. A 4.0 MHz PMN-PT transducer array (with 16 elements) was fabricated and tested in a pulse-echo arrangement. A -6 dB bandwidth of 110% and two-way insertion loss of -46.5 dB were achieved.
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25
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Tsang MB, Lee J, Su SC, Dai JY, Horoi M, Liu H, Lynch WG, Warren S. Survey of excited state neutron spectroscopic factors for Z=8-28 nuclei. Phys Rev Lett 2009; 102:062501. [PMID: 19257580 DOI: 10.1103/physrevlett.102.062501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2008] [Indexed: 05/27/2023]
Abstract
We have extracted 565 neutron spectroscopic factors of sd and fp shell nuclei by systematically analyzing more than 2000 measured (d, p) angular distributions. We are able to compare 125 of the extracted spectroscopic factors to values predicted by large-basis shell-model calculations and evaluate the accuracies of spectroscopic factors predicted by different shell-model interactions in these regions. We find that the spectroscopic factors predicted for most excited states of sd-shell nuclei using the latest USDA or USDB interactions agree with the experimental values. For fp shell nuclei, the inability of the current models to account for the core excitation and fragmentation of the states leads to considerable discrepancies. In particular, the agreement between data and shell-model predictions for Ni isotopes is not better than a factor of 2 using either the GXPF1A or the XT interaction.
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Affiliation(s)
- M B Tsang
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
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26
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Chakraborty G, Sarkar CK, Lu XB, Dai JY. Study of the tunnelling initiated leakage current through the carbon nanotube embedded gate oxide in metal oxide semiconductor structures. Nanotechnology 2008; 19:255401. [PMID: 21828650 DOI: 10.1088/0957-4484/19/25/255401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The tunnelling currents through the gate dielectric partly embedded with semiconducting single-wall carbon nanotubes in a silicon metal-oxide-semiconductor (MOS) structure have been investigated. The application of the gate voltage to such an MOS device results in the band bending at the interface of the partly embedded oxide dielectric and the surface of the silicon, initiating tunnelling through the gate oxide responsible for the gate leakage current whenever the thickness of the oxide is scaled. A model for silicon MOS structures, where carbon nanotubes are confined in a narrow layer embedded in the gate dielectric, is proposed to investigate the direct and the Fowler-Nordheim (FN) tunnelling currents of such systems. The idea of embedding such elements in the gate oxide is to assess the possibility for charge storage for memory device applications. Comparing the FN tunnelling onset voltage between the pure gate oxide and the gate oxide embedded with carbon nanotubes, it is found that the onset voltage decreases with the introduction of the nanotubes. The direct tunnelling current has also been studied at very low gate bias, for the thin oxide MOS structure which plays an important role in scaling down the MOS transistors. The FN tunnelling current has also been studied with varying nanotube diameter.
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Affiliation(s)
- Gargi Chakraborty
- Department of Electronics and Telecommunication Engineering, Jadavpur University, Kolkata, India
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27
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Wang S, Liu W, Zhang M, Song Z, Lin C, Dai JY, Lee PF, Chan HLW, Choy CL. Negative photoconductivity and memory effects of germanium nanocrystals embedded in HfO2 dielectric. J Nanosci Nanotechnol 2006; 6:205-8. [PMID: 16578903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
A metal-insulator-semiconductor (MIS) structure containing an HfO2/SiO2 stack tunnel layer, isolated Germanium (Ge) nanocrystals, and an HfO2 capping layer, was obtained by an electron-beam evaporation method. A high-resolution transmission electron microscopy (HRTEM) study revealed that uniform and pronounced Ge nanocrystals had formed after annealing. Raman spectroscopy provided evidence for the formation of Ge-Ge bonds and the optimal annealing temperature for the crystallization ratio of the Ge. The electric properties of the MIS structure were characterized by capacitance-voltage (C-V) and current-voltage (I-V) measurements at room temperature. Negative photoconductivity was observed when the structure was under a forward bias, which screened the bias voltage, resulting in a decrease in the current at a given voltage and a negative shift in flat band voltage. A relatively high stored charge density of 3.27 x 10(12) cm 2 was also achieved.
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Affiliation(s)
- Shiye Wang
- The Research Center of Semiconductor Functional Film Engineering Technology, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, PR China
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28
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Tang DP, Yuan R, Chai YQ, Zhong X, Liu Y, Dai JY, Zhang LY. Novel potentiometric immunosensor for hepatitis B surface antigen using a gold nanoparticle-based biomolecular immobilization method. Anal Biochem 2004; 333:345-50. [PMID: 15450811 DOI: 10.1016/j.ab.2004.06.035] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2004] [Indexed: 11/23/2022]
Abstract
A novel potentiometric immunosensor for the detection of hepatitis B surface antigen has been developed by means of self-assembly to immobilize hepatitis B surface antibody on a platinum disk electrode based on gold nanoparticles, Nafion, and gelatin as matrices in this study. The modification procedure of the immunosensor was further characterized by using cyclic voltammetry and the enzyme-linked immunosorbent assay (ELISA) method. The detection is based on the change in the electric potential before and after the antigen-antibody reaction. In contrast to the commonly applied methods (e.g., the glutaraldehyde crosslinking procedure), this strategy could allow for antibodies immobilized with a higher loading amount and better retained immunoactivity, as demonstrated by the potentiometric measurements. A dynamic concentration range of 4-800 ng ml(-1) and a detection limit of 1.3 ng ml(-1) were observed. Analytical results of several human serum samples obtained using the developing technique are in satisfactory agreement with those given by ELISA. In addition, the technique presents some distinct advantages over the traditional sandwich format in that the analyzing performances are direct, rapid, and simple without multiple separation and labeling steps.
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Affiliation(s)
- D P Tang
- College of Chemistry Chemical Engineering, Southwest Normal University, Chongqing 400715, People's Republic of China
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29
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Gong GL, Cheng GB, Hu JH, Dai JY. [Determination of elemenyl piperidine salt in water by capillary gas chromatography]. Se Pu 2000; 18:335-6. [PMID: 12541511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023] Open
Abstract
beta-Elemene and its derivatives were hopeful new antitumor drugs. A method for determination of elemenyl piperidine salt in water has been developed with capillary gas chromatography. The samples were neutralized by sodium carbonate and extracted by n-heptane. n-Octadecane was used as the internal standard. The linear range was from 10 g/L to 100 g/L, with a correlation coefficient of 0.9998. The average recovery of the method was 99.96% and the RSD was 0.46% (n = 5). The coefficient of variation was less than 2%. The method is simple, rapid, accurate and can be applied to the determination of the nitrogen-containing compounds of beta-elemene.
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Affiliation(s)
- G L Gong
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
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30
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Jin LJ, Wei Z, Dai JY, Guo P, Wang LS. Prediction of partitioning properties for benzaldehydes by various molecular descriptors. Bull Environ Contam Toxicol 1998; 61:1-7. [PMID: 9657823 DOI: 10.1007/s001289900721] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Affiliation(s)
- L J Jin
- Department of Environmental Science and Engineering, Nanjing University, Peoples' Republic of China
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31
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Li SW, Sun HL, Lu XJ, Zhang SY, Lu FL, Dai JY, Xu YB. [Synthesis of cephalotaxine esters and their antitumor activity (author's transl)]. Yao Xue Xue Bao 1981; 16:821-7. [PMID: 7342677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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