通讯机构：
[Hongyi Zhu] P;[Shulin Sun] S;Peng Cheng Laboratory , Shenzhen 518055, China<&wdkj&>Shanghai Engineering Research Center of Ultra-Precision Optical Manufacturing, Department of Optical Science and Engineering, School of Information Science and Technology, Fudan University , Shanghai 200433, China
期刊：
Chemical Physics Letters,2022年802:139752 ISSN：0009-2614
通讯作者：
Wei, Xiaolin(xlw@xtu.edu.cn)
作者机构：
[Cao, Jingyi; Zhang, Qi; Yao, Yongsheng; Cao, Juexian; Wei, Xiaolin] Department of Physics and Laboratory for Quantum Engineering and Micro-Nano Energy Technology, Xiangtan University, Hunan, Xiangtan;411105, China;College of Physics and Electronics Engineering, Hengyang Normal University, Hengyang;421002, China;[Yin, Wenjin] School of Physics and Electronic Science, Hunan University of Science and Technology, Xiangtan
通讯机构：
[Xiaolin Wei] D;Department of Physics and Laboratory for Quantum Engineering and Micro-Nano Energy Technology, Xiangtan University, Xiangtan 411105, Hunan, China<&wdkj&>College of Physics and Electronics Engineering, Hengyang Normal University, Hengyang 421002, China
摘要：
Many multi-objective optimization problems in reality are dynamic, requiring the optimization algorithm to quickly track the moving optima after the environment changes. Therefore, response strategies are often used in dynamic multi-objective algorithms to find Pareto optimal. In this paper, we propose a hybrid prediction strategy based on the classification of decision variables, which consists of three steps. After detecting the environment change, the first step is to analyze the influence of each decision variable on individual convergence and distribution in the new environment. The second step is to adopt different prediction methods for different decision variables. Finally, adaptive selection is applied to the solution set generated in the first and second steps, and solutions with good convergence and diversity are selected to make the initial population more adaptable to the new environment. The prediction strategy can help the solution set converge while maintaining its diversity. The experimental results and performance show that the proposed algorithm is capable of significantly improving the dynamic optimization performance compared with five state-of-the-art evolutionary algorithms.
作者机构：
[Wang, Haibin; He, Xiongying; Shi, Yimin; Zhou, Zheng] Hunan Inst Technol, Dept Phys, Hengyang 421002, Peoples R China.;[Tang, Shiqing] Hengyang Normal Univ, Coll Phys & Elect Engn, Hengyang 421002, Peoples R China.;[Deng, Haiming] Xiangnan Univ, Sch Elect Informat & Elect Engn, Chenzhou 423000, Peoples R China.;[Zhong, Honghua] Cent South Univ Forestry & Technol, Inst Math & Phys, Changsha 410004, Peoples R China.
通讯机构：
[Honghua Zhong] I;Institute of Mathematics and Physics, Central South University of Forestry and Technology, Changsha 410004, China
关键词：
Bose-Einstein condensates;Quantum droplets;Three-body recombination loss
摘要：
We investigate the dynamics of dissipative quantum droplets (QDs) forming in one-dimensional binary Bose gases subjected to three-body recombination loss and linear gain in perturbed optical lattices. We demonstrate by a perturbation procedure that an alimentation of atoms from an external feeding source to the QDs may lead to the formation of dynamically-stabilized dissipation-controlled QDs. It is worth noting that such dissipation-controlled QDs are independent of the initial condensation norm and are solely determined by the gain and loss parameters. We further study the dynamics of the dissipation controlled QDs with varying norm due to the gain and loss mechanisms in relatively weak optical lattices. It is found that the stationary dissipative QDs can be accelerated and either continuously travel across the potential barriers or eventually perform trapped oscillations in different lattice sites by selecting the appropriate gain and loss parameters. Finally, we deal with the collision between the dissipative QDs. It is revealed that two slowly moving dissipative QDs with varying norm may merge or collide quasi-elastically depending on their initial separation, which is quite different from QDs in the conservative systems. Specially, we explore the collision dynamics of the dissipative QDs in a single lattice site provided that the spatial period of optical lattices is large enough. The in-phase interaction between the dissipative QDs tends to merge, while the out-of-phase interaction displays quasi-elastic collision. (c) 2021 Elsevier Ltd. All rights reserved.
通讯机构：
[Luo, X.-J.] S;[Tang, S.-L.] N;Nanjing National Laboratory of Microstructures, China;Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric PowerChina
关键词：
transport properties;molecular electronic devices;nonequilibrium Green's functions
摘要：
Dynamically controlling terahertz (THz) wavefronts in a designable fashion is highly desired in practice. However, available methods working at microwave frequencies do not work well in the THz regime due to lacking suitable tunable elements with submicrometer sizes. Here, instead of locally controlling individual meta-atoms in a THz metasurface, we show that rotating different layers (each exhibiting a particular phase profile) in a cascaded metadevice at different speeds can dynamically change the effective Jones-matrix property of the whole device, thus enabling extraordinary manipulations on the wavefront and polarization characteristics of a THz beam impinging on the device. After illustrating our strategy based on model calculations, we experimentally demonstrate two proof-of-concept metadevices, each consisting of two carefully designed all-silicon transmissive metasurfaces exhibiting different phase profiles. Rotating two metasurfaces inside the fabricated devices at different speeds, we experimentally demonstrate that the first metadevice can efficiently redirect a normally incident THz beam to scan over a wide solid-angle range, while the second one can dynamically manipulate both the wavefront and polarization of a THz beam. Our results pave the way to achieving dynamic control of THz beams, which is useful in many applications, such as THz radar, and bio- and chemical sensing and imaging.
作者机构：
[李浪; 冯景亚; 刘波涛; 郭影; 李秋萍] Hunan Provincial Key Laboratory of Intelligent Information Processing and Application, Hengyang Normal University, Hengyang;421002, China;College of Information Science and Engineering, Hunan Normal University, Changsha;410081, China;College of Computer Science and Technology, Hengyang Normal University, Hengyang
通讯机构：
[Jingya Feng] H;Hunan Provincial Key Laboratory of Intelligent Information Processing and Application, Hengyang Normal University, Hengyang, China<&wdkj&>College of Information Science and Engineering, Hunan Normal University, Changsha, China
摘要：
In this era of pervasive computing, low-resource devices have been deployed in various fields. PRINCE is a lightweight block cipher designed for low latency, and is suitable for pervasive computing applications. In this paper, we propose new circuit structures for PRINCE components by sharing and simplifying logic circuits, to achieve the goal of using a smaller number of logic gates to obtain the same result. Based on the new circuit structures of components and the best sharing among components, we propose three new hardware architectures for PRINCE. The architectures are simulated and synthesized on different programmable gate array devices. The results on Virtex-6 show that compared with existing architectures, the resource consumption of the unrolled, low-cost, and two-cycle architectures is reduced by 73, 119, and 380 slices, respectively. The low-cost architecture costs only 137 slices. The unrolled architecture costs 409 slices and has a throughput of 5.34 Gb/s. To our knowledge, for the hardware implementation of PRINCE, the new low-cost architecture sets new area records, and the new unrolled architecture sets new throughput records. Therefore, the newly proposed architectures are more resource-efficient and suitable for lightweight, latency-critical applications.
摘要：
With exceptional electrical and mechanical properties and at the same time air-stability, layered MoSi2N4 has recently drawn great attention. However, band structure engineering via strain and electric field, which is vital for practical applications, has not yet been explored. In this work, we show that the biaxial strain and external electric field are effective ways for the bandgap engineering of bilayer MoSi2N4 and WSi2N4. It is found that strain can lead to indirect bandgap to direct bandgap transition. On the other hand, electric field can result in semiconductor to metal transition. Our study provides insights into the band structure engineering of bilayer MoSi2N4 and WSi2N4 and would pave the way for its future nanoelectronics and optoelectronics applications.
期刊：
Fusion Engineering and Design,2021年172:112897 ISSN：0920-3796
通讯作者：
Li, Xinxia
作者机构：
[Li, Xinxia; Li, Guozhuang; Liu, Hongbo] Univ South China, Dept Nucl Phys, Hengyang 421001, Peoples R China.;[Li, Xinxia] Chinese Acad Sci, Inst Plasma Phys, Hefei 230031, Peoples R China.;[Liu, Hongbo] HengYang Normal Univ, Coll Phys & Elect Engn, Hengyang 421008, Peoples R China.
通讯机构：
[Li, Xinxia] U;Univ South China, Dept Nucl Phys, Hengyang 421001, Peoples R China.
关键词：
CFETR;Helicon wave;Plasma current drive;Tokamak
摘要：
The China Fusion Engineering Testing Reactor (CFETR) is a tokamak reactor and aims to eventually reach DEMO relevant fusion power level of 1 GW. A lower single null configuration of the divertor design is proposed for the machine. To obtain the high performance operation of the plasma, both the hybrid and steady-state operating scenarios are suggested. In these scenarios, the plasma beta of <beta(e)> similar to 1.6% has been generally reached. In the paper, helicon wave propagation and current drive in CFETR are studied through GENRAY/CQL3D code. An analysis of the wave damping factor in CFETR plasma indicates that the electron Landau damping is dominant for the core plasma. According to the dimensionless parameter xi(e) and beta(e), a strong wave damping region is found. Based on the GENRAY simulation, the single pass power absorptions are generally obtained in both scenarios. Scanning of generated current on the launched poloidal angle indicates that high current drive efficiency is produced at theta similar to 30 degrees. For helicon wave with frequency f = 700 MHz, calculations of the current drive show that off-axis current drive about 30 kA/MW and 50 kA/MW are obtained in the hybrid and steady-state scenarios respectively. Simultaneously, the lower plasma density and high temperature promote the high current generation. Moreover, the obtained current drive and its peak position are shown to be sensitive to the launched n(//) similar to Finally, the helicon wave with frequency f = 700 MHz and launched n(//) similar to 2.0-3.0 is proposed to be a promising scheme for effective off-axis current drive in CFETR.
作者机构：
[Wang, Yanzhao; Xu, He-Xiu; Wang, Chaohui] Air Force Engn Univ, Air & Missile Def Coll, Xian 710051, Peoples R China.;[Xu, He-Xiu; Huang, Wei] Northwestern Polytech Univ, Inst Flexible Elect, Xian 710072, Peoples R China.;[Xu, He-Xiu; Ling, Xiaohui] Hengyang Normal Univ, Coll Phys & Elect Engn, Hengyang 421002, Peoples R China.;[Qiu, Cheng-Wei; Hu, Guangwei] Natl Univ Singapore, Dept Elect & Comp Engn, Singapore 117583, Singapore.;[Tang, Shiwei] Ningbo Univ, Fac Sci, Dept Phys, Ningbo 315211, Peoples R China.
通讯机构：
[He-Xiu Xu] A;[Wei Huang] I;[Cheng-Wei Qiu] D;Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583 Singapore<&wdkj&>Air and Missile Defense College, Air force Engineering University, Xi'an, 710051 China<&wdkj&>Institute of Flexible Electronics, Northwestern Polytechnical University, Xi'an, 710072 China<&wdkj&>College of Physics and Electronic Engineering, Hengyang Normal University, Hengyang, 421002 China<&wdkj&>Institute of Flexible Electronics, Northwestern Polytechnical University, Xi'an, 710072 China
摘要：
A two-dimensional (2D) MoSi2N4 monolayer is an emerging class of air-stable 2D semiconductors possessing exceptional electrical and mechanical properties. Despite intensive recent research effort devoted to uncover the material properties of MoSi2N4, the physics of electrical contacts to MoSi2N4 remains largely unexplored thus far. In this work, we study van der Waals heterostructures composed of MoSi2N4 contacted by graphene and NbS2 monolayers using first-principles density functional theory calculations. We show that the MoSi2N4/NbS2 contact exhibits an ultralow Schottky barrier height (SBH), which is beneficial for nanoelectronics applications. For the MoSi2N4/graphene contact, the SBH can be modulated via the interlayer distance or via external electric fields, thus opening up an opportunity for reconfigurable and tunable nanoelectronic devices. Our findings provide insights into the physics of 2D electrical contacts to MoSi2N4 and shall offer a critical first step toward the design of high-performance electrical contacts to MoSi2N4-based 2D nanodevices.
