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Chinese Physics B 2024年第6期33卷 596-603页

作者：吕小龙杨加恩谢航 College of Science Guangxi University of Science and TechnologyLiuzhou 545006China College of Physics Chongqing UniversityChongqing 401331China Chongqing Key Laboratory for Strongly-Coupled Physics Chongqing UniversityChongqing 401331China

Topological zero-line modes(zLMs) with spin and valley degrees of freedom give rise to spin, valley and spinvalley transport, which support a platform for exploring quantum transport physics and potential applications in spintronic/valleytronic devices. In this work, we investigate the beam-splitting behaviors of the charge current due to the zLMs in a three-terminal system. We show that with certain combinations of zLMs, the incident charge current along the interface between different topological phases can be divided into different polarized currents with unit transmittance in two outgoing terminals. As a result, fully spin-polarized, valley-polarized and spin-valley-polarized electron beam splitters are generated. The mechanism of these splitters is attributed to the cooperative effects of the distribution of the zLMs and the intervalley and intravalley scatterings that are modulated by the wave-vector mismatch and group velocity mismatch. Interestingly, half-quantized transmittance of these scatterings is found in a fully spin-valley-polarized electron beam ***, the results indicate that these splitters can be applicable to graphene, silicene, germanene and stanene due to their robustness against the spin–orbit coupling. Our findings offer a new way to understand the transport mechanism and investigate the promising applications of zLMs.

关键词： topological zero-line modes spin polarization valley polarization quantum transport

Extensive numerical simulations on competitive growth between the Edwards–Wilkinson and Kardar–Parisi–zhang universality classes

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Chinese Physics B 2024年第6期33卷 298-307页

作者：余成志刘潇唐军夏辉 School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221116China

Extensive numerical simulations and scaling analysis are performed to investigate competitive growth between the linear and nonlinear stochastic dynamic growth systems, which belong to the Edwards–Wilkinson(EW) and Kardar–Parisi–zhang(KPz) universality classes, respectively. The linear growth systems include the EW equation and the model of random deposition with surface relaxation(rDSr), the nonlinear growth systems involve the KPz equation and typical discrete models including ballistic deposition(BD), etching, and restricted solid on solid(rSOS). The scaling exponents are obtained in both the(1 + 1)-and(2 + 1)-dimensional competitive growth with the nonlinear growth probability p and the linear proportion 1-p. Our results show that, when p changes from 0 to 1, there exist non-trivial crossover effects from EW to KPz universality classes based on different competitive growth rules. Furthermore, the growth rate and the porosity are also estimated within various linear and nonlinear growths of cooperation and competition.

关键词： competitive growth scaling behavior discrete growth model Kardar–Parisi–zhang universality class

Decoding the inconsistency of six cropland maps in China

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The Crop Journal 2024年第1期12卷 281-294页

作者： Yifeng Cui ronggao Liu zhichao Li Chao zhang xiao-Peng Song Jilin Yang Le Yu Mengxi Chen Jinwei Dong Institute of Geographic Sciences and Natural resources research Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Department of Geographical Sciences University of MarylandCollege ParkMD 20740USA College of Grassland Science and Technology China Agricultural UniversityBeijing 100193China Ministry of Education Ecological Field Station for East Asian Migratory Birds Department of Earth System ScienceInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China Ministry of Education Ecological Field Station for East Asian Migratory Birds Beijing 100084China Tsinghua University(Department of Earth System Science)-Xi’an Institute of Surveying and Mapping Joint research Center for Next-Generation Smart Mapping Beijing 100084China Institute of remote Sensing and Geographic Information System Peking UniversityBeijing 100871China Department of Forest and Conservation Sciences University of British ColumbiaVancouverBCV6T 1Z4Canada

Accurate cropland information is critical for agricultural planning and production,especially in foodstressed countries like *** widely used medium-to-high-resolution satellite-based cropland maps have been developed from various remotely sensed data sources over the past few decades,considerable discrepancies exist among these products both in total area and in spatial distribution of croplands,impeding further applications of these *** factors influencing their inconsistency are also *** this study,we evaluated the consistency and accuracy of six cropland maps widely used in China in circa 2020,including three state-of-the-art 10-m products(i.e.,Google Dynamic World,ESrI Land Cover,and ESA WorldCover)and three 30-m ones(i.e.,GLC_FCS30,GlobeLand 30,and CLCD).We also investigated the effects of landscape fragmentation,climate,and agricultural *** using a ground-truth sample revealed that the 10-m-resolution WorldCover provided the highest accuracy(92.3%).These maps collectively overestimated Chinese cropland area by up to 56%.Up to 37%of the land showed spatial inconsistency among the maps,concentrated mainly in mountainous regions and attributed to the varying accuracy of cropland maps,cropland fragmentation and management practices such as *** work shed light on the promotion of future cropland mapping efforts,especially in highly inconsistent regions.

关键词： Consistency and accuracy 10-and 30 m Cropland mapping Agricultural management China

Activation and polarization of striatal microglia and astrocytes are involved in bradykinesia and allodynia in early-stage parkinsonian mice

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Fundamental research 2024年第4期4卷 806-819页

作者： Xue zhang zi-Lin Shen Ya-Wei Ji Cui Yin Cheng xiao Chunyi zhou Jiangsu Province Key Laboratory of Anesthesiology School of AnesthesiologyXuzhou Medical UniversityXuzhou 221004China Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology Xuzhou Medical UniversityXuzhou 221004China NMPA Key Laboratory for research and Evaluation of Narcotic and Psychotropic Drugs School of AnesthesiologyXuzhou Medical UniversityXuzhou 221004China

In addition to the cardinal motor symptoms,pain is a major non-motor symptom of Parkinson's disease(PD).Neuroinflammation in the substantia nigra pars compacta and dorsal striatum is involved in neurodegeneration in *** the polarization of microglia and astrocytes in the dorsal striatum and their contribution to motor deficits and hyperalgesia in PD have not been *** the present study,we observed that hemiparkinsonian mice established by unilateral 6-OHDA injection in the medial forebrain bundle exhibited motor deficits and mechanical *** these mice,both microglia and astrocytes in the dorsal striatum were activated and polarized to M1/M2 microglia and A1/A2 astrocytes as genes specific to these cells were *** effects peaked 7 days after 6-OHDA ***,striatal astrocytes in parkinsonian mice also displayed hyperpolarized membrane potentials,enhanced voltage-gated potassium currents,and dysfunction in inwardly rectifying potassium channels and glutamate *** administration of minocycline,a microglia inhibitor,attenuated the expression of genes specific to M1 microglia and A1 astrocytes in the dorsal striatum(but not those specific to M2 microglia and A2 astrocytes),attenuated the damage in the nigrostriatal dopaminergic system,and alleviated the motor deficits and mechanical allodynia in parkinsonian *** contrast,local administration of minocycline into the dorsal striatum of parkinsonian mice mitigated only *** study suggests that M1 microglia and A1 astrocytes in the dorsal striatum may play important roles in the development of pathophysiology underlying hyperalgesia in the early stages of PD.

关键词： Parkinson's disease Dopaminergic system Striatum Microglia Astrocytes Substantia nigra pars compacta

Light-emitting devices based on atomically thin MoSe_(2)

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Journal of Semiconductors 2024年第4期45卷 19-35页

作者： Xinyu zhang Xuewen zhang Hanwei Hu Vanessa Li zhang Weidong xiao Guangchao Shi Jingyuan Qiao Nan Huang Ting Yu Jingzhi Shang Institute of Flexible Electronics Northwestern Polytechnical UniversityXi'an 710129China School of Physics and Technology Wuhan UniversityWuhan 430072China Wuhan Institute of Quantum Technology Wuhan 430206China

Atomically thin MoSe_(2) layers,as a core member of the transition metal dichalcogenides(TMDs)family,benefit from their appealing properties,including tunable band gaps,high exciton binding energies,and giant oscillator strengths,thus pro-viding an intriguing platform for optoelectronic applications of light-emitting diodes(LEDs),field-effect transistors(FETs),sin-gle-photon emitters(SPEs),and coherent light sources(CLSs).Moreover,these MoSe_(2) layers can realize strong excitonic emis-sion in the near-infrared wavelengths,which can be combined with the silicon-based integration technologies and further encourage the development of the new generation technologies of on-chip optical interconnection,quantum computing,and quantum information ***,we overview the state-of-the-art applications of light-emitting devices based on two-dimensional MoSe_(2) ***,we introduce recent developments in excitonic emission features from atomically thin MoSe_(2) and their dependences on typical physical ***,we focus on the exciton-polaritons and plasmon-exciton polaritons in MoSe_(2) coupled to the diverse forms of optical ***,we highlight the promising applications of LEDs,SPEs,and CLSs based on MoSe_(2) and their ***,we summarize the challenges and opportunities for high-quality emis-sion of MoSe_(2) and high-performance light-emitting devices.

关键词： MoSe_(2) light-matter interaction exciton polariton light-emitting device

Solid-state non-volatile memories based on vdW heterostructure-based vertical-transport ferroelectric field-effect transistors

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Science China(Information Sciences) 2024年第6期67卷 198-206页

作者： Qiyu YANG zheng-Dong LUO Fei xiao Junpeng zHANG Dawei zHANG Dongxin TAN Xuetao GAN Yan LIU zhufei CHU Yinshui XIA Genquan HAN Hangzhou Institute of Technology Xidian University State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology School of MicroelectronicsXidian University School of Artificial Intelligence Xidian University School of Materials Science and Engineering University of New South Wales (UNSW) Sydney ArC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET) University of New South Wales (UNSW) Sydney Key Laboratory of Light Field Manipulation and Information Acquisition Ministry of Industry and Information Technologyand Shaanxi Key Laboratory of Optical Information TechnologySchool of Physical Science and TechnologyNorthwestern Polytechnical University Faculty of Electrical Engineering and Computer Science Ningbo University

Driven by the explosive development of data-centric computation applications, it is becoming urgent to develop in-memory computing devices that are beyond the von Neumann architecture with an arrangement of separated logic and memory components. The transistor-type solid-state non-volatile memories,such as ferroelectric field-effect transistors(Fe FETs), have long been regarded as a competitive candidate for future in-memory computing architectures. However, the density scaling towards high-density arrays would require advanced Fe FETs with reduced footprints, which remains a great challenge so far. Here, a vertical-transport(VT) Fe FET that flips the charge transport channel perpendicular to the substrate plane is proposed, in which a ferroelectric gate and a van der Waals(vd W) heterojunction channel are vertically integrated, effectively reducing the device footprints. The proposed VT-Fe FET shows not only the robust binary non-volatile memory states but also several key synaptic functionalities at the device level. An artificial neural network with supervised learning was simulated based on the device conductance switching properties,showing excellent classification accuracy for the MNIST handwritten digits. These findings suggest that the proposed VT-Fe FET could offer a new solution for future non-volatile memories as well as more advanced neuromorphic systems.

关键词： vdW heterostructure non-volatile memory vertical-transport transistor ferroelectric field-effect transistor memristive devices

The preparation and performance analysis of zirconium-modified aluminum phosphate-based high-temperature(rT-1500℃)resistant adhesive for joining alumina in extreme environment

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Journal of Advanced Ceramics 2024年第7期13卷 911-932页

作者： Jingxuan Liu Yange Wan Bo xiao Jiancun Li zhanming Hu ruoyu zhang xiaoxia Hu Jiachen Liu Guoshuai Cai Hongli Liu Mingchao Wang College of Science Civil Aviation University of ChinaTianjin 300300China Department of Safety Engineering Civil Aviation University of ChinaTianjin 300300China Binzhou Beicheng Construction Engineering Materials Testing Co. Ltd.Binzhou 256602China Department of Aviation Engineering Civil Aviation University of ChinaTianjin 300300China School of Materials and Engineering Key Lab of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin UniversityTianjin 300072China

High-temperature-resistant adhesives are critical materials in the aerospace *** zirconium-modified aluminum phosphate-based adhesives developed in this work had the advantage of adjustable thermal expansibility,achieving a high matching of coefficient of thermal expansion(CTE)with *** introduction of zirconium can significantly improve the thermal stability of the adhesive matrix,and the zr/Al ratio substantially affects the various reaction processes inside the adhesive,especially the types of zirconium-containing *** of the zirconium-containing compounds in the A7z3 adhesive were zrO_(2) only when the mass ratio of zirconium hydroxide to aluminum hydroxide was 3:7,which was the key reason why it had the highest *** room-temperature bonding strength of A7z3 after heat treatment at 1500℃reached 67.2 *** pretreatment at 1500℃,the high-temperature bonding strength of A7z3 was greater than 50 MPa in the range of(room temperature)rT-1000℃.After 40 thermal cycles between rT and 1500℃,the bonding strength still reached 10 *** bonding occurred at temperatures below 1000℃,while chemical bonding dominated above 1000℃based on the generation of Al5BO9 and mullite at the interfaces.

关键词： high-temperature-resistant adhesive thermal expansion property zirconium-modified aluminum phosphate bonding performance thermal cycling bonding mechanism

Pluggable multitask diffractive neural networks based on cascaded metasurfaces

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Opto-Electronic Advances 2024年第2期7卷 23-31页

作者： Cong He Dan zhao Fei Fan Hongqiang zhou Xin Li Yao Li Junjie Li Fei Dong Yin-xiao Miao Yongtian Wang Lingling Huang Beijing Engineering research Center of Mixed reality and Advanced Display Key Laboratory of Photoelectronic Imaging Technology and System of Ministry of Education of ChinaSchool of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China Institute of Modern Optics Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network TechnologyNankai UniversityTianjin 300350China Department of Physics and Optoelectronics Faculty of ScienceBeijing University of TechnologyBeijing 100124China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100191China Beijing Aerospace Institute for Metrology and Measurement Technology Beijing 100076China

Optical neural networks have significant advantages in terms of power consumption,parallelism,and high computing speed,which has intrigued extensive attention in both academic and engineering *** has been considered as one of the powerful tools in promoting the fields of imaging processing and object ***,the existing optical system architecture cannot be reconstructed to the realization of multi-functional artificial intelligence systems *** push the development of this issue,we propose the pluggable diffractive neural networks(P-DNN),a general paradigm resorting to the cascaded metasurfaces,which can be applied to recognize various tasks by switching internal *** the proof-of-principle,the recognition functions of six types of handwritten digits and six types of fashions are numerical simulated and experimental demonstrated at near-infrared ***,the proposed paradigm not only improves the flexibility of the optical neural networks but paves the new route for achieving high-speed,low-power and versatile artificial intelligence systems.

关键词： optical neural networks diffractive deep neural networks cascaded metasurfaces

Geometry characteristics and wide temperature behavior of silicon-based GaN surface acoustic wave resonators with ultrahigh quality factor

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Science China(Information Sciences) 2024年第2期67卷 267-278页

作者： Guofang YU renrong LIANG Haiming zHAO Lei xiao Jie CUI Yue zHAO Wenpu CUI Jing WANG Jun XU Jun FU Tianling rEN School of Integrated Circuits Tsinghua University Beijing National research Center for Information Science Technology Tsinghua University

Surface acoustic wave(SAW) resonators with an ultrahigh Q-factor are designed and fabricated on silicon-based gallium nitride(GaN/Si). The temperature-dependent performance is characterized over a wide range, from 10 to 500 K. Finite element analysis is employed to guide the design of the SAW resonator from indications of the rayleigh mode and weak propagation direction dependence of SAW in the c-plane of GaN/Si. The SAW resonator with 100 pairs of interdigital transducers(IDT), 100 pairs of grating reflectors(Gr) for each side, aperture size of 80 μm, metallization ratio of 0.5, and electrode width of 500 nm resonates at 1.9133 GHz accordingly with an ultrahigh Q-factor of 7622 at room temperature, which contributes the fr× Qr, up to 14.583×1012Hz. A resonator operating over 10 to 500 K indicates an approximately linear decreasing temperature dependence above 280 K while being approximately constant below 40 K. The fitting to resonator characteristics using the modified Butterworth Van Dyke(m BVD) model reveals a reduction in both the electrode and mechanical losses while worsening the dielectric loss with cooling down.

关键词： GaN/Si SAW resonator ultrahigh Q-factor temperature-dependent performance mBVD losses

Magnesium-containing pellet regulating blast furnace ferrous burden interaction:softening-melting behavior and mechanism

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Journal of Iron and Steel research International 2024年第7期31卷 1623-1635页

作者： Li-ming Ma Jian-liang zhang Yao-zu Wang xiao-yong Ma Gui-lin Wang zhuo Li Hui-qing Jiang zheng-jian Liu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing 100083China Lingyuan Iron and Steel Group Co. Lingyuan 122500LiaoningChina

MgO participates in all stages of sintering,pelletizing,and blast furnace ironmaking,and synergistically optimizing the distribution of MgO in ferrous burden can effectively enhance the interaction within the ferrous burdens and optimize the softening-melting properties of the mixed ***-containing pellets mixed with low-MgO sinter or mixed with high-MgO sinter in the blast furnace ferrous burden structure have opposite softening-melting performance *** the structure of the ferrous burden is magnesium-containing pellets mixed with low-MgO sinter,the magnesium-containing pellets can enhance the interaction of the ferrous burden in the process of softening-melting,which can optimize the composition of the slag phase and improve the slag *** the structure of the ferrous burden is magnesium-containing pellets mixed with high-MgO sinter,the magnesium-containing pellets weaken the interaction of the ferrous burden in the process of softening-melting,increase the content of the high melting point solid-phase particles in the slag,lead to an increase in the viscosity of the slag and difficult separation of the slag and iron,and decrease the permeability of the charge ***,to ensure good permeability of the mixed burden,the following measures are suggested:optimizing the MgO distribution of the ferrous burden,reducing the MgO content of the sinter to 1.96 wt.%,increasing the MgO content of the pellets to 1.03-1.30 wt.%,controlling the MgO/Al_(2)O_(3) ratio of the mixed burden within 1.15-1.32,narrowing the position of the cohesive zone,and maintaining an S value(permeability index)of approximately 150 kPa℃.

关键词： Ironmaking Ferrous burden Softening-melting property Interaction Permeability Slag