检索结果-内蒙古大学图书馆

arXiv 2022年

作者： Zou, Bo Zhou, Yu Zhou, Yan Wu, Yanyan He, Yang Wang, Xiaonan Yang, Jinfeng Zhang, Lianghui Chen, Yuxiang Zhou, Shi Guo, Huaixin Sun, Huarui School of Science Ministry of Industry and Information Technology Key Laboratory of Micro-Nano Optoelectronic Information System Harbin Institute of Technology Shenzhen518055 China Collaborative Innovation Center of Extreme Optics Shanxi University Shanxi Taiyuan030006 China State Key Laboratory of Superlattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences Beijing100083 China University of Science and Technology of China Hefei230026 China Science and Technology on Monolithic Integrated Circuits and Modules Laboratory Nanjing Electronic Devices Institute Nanjing210016 China

The emerging Au-assisted exfoliation technique provides a wealth of large-area and high-quality ultrathin two-dimensional (2D) materials compared with traditional tape-based exfoliation. Fast, damage-free, and reliable determination of the layer number of such 2D films is essential to study layer-dependent physics and promote device applications. Here, an optical method has been developed for simple, high throughput, and accurate determination of the layer number for Au-assisted exfoliated MoS2 and WS2 films in a broad thickness range. The method is based on quantitative analysis of layer-dependent white light reflection spectra, revealing that the reflection peak intensity can be used as a clear indicator for determining the layer number. The simple yet robust method will facilitate the fundamental study on layer-dependent optical, electrical, and thermal properties and device applications of 2D materials. The technique can also be readily combined with photoluminescence and Raman spectroscopies to study other layer-dependent physical properties of 2D materials. Copyright © 2022, The Authors. All rights reserved.

关键词： Layered semiconductors

来源：评论

学校读者我要写书评

暂无评论

Scaling Solar Photocatalytic Hydrogen Production in China: Integrated Geospatial-Meteorological Analysis

SSRN

引用

SSRN 2024年

作者： Li, Yinan Li, Lanyu Yuan, Hongkuan He, Keji Chen, Hong Xie, Jianping Wang, Biao Wang, Xiaonan School of Physical Science and Technology Southwest University Chongqing400715 China Department of Chemical and Biomolecular Engineering National University of Singapore Singapore117585 Singapore Department of Chemical Engineering Tsinghua University Beijing100084 China China Oilfield Services Limited Yanjiao065201 China Center for Research on Intelligent Perception and Computing National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing100190 China School of Artificial Intelligence University of Chinese Academy of Sciences Beijing101408 China School of Resources and Environment Institute of Fundamental and Frontier Science University of Electronic Science and Technology of China Chengdu611731 China Chongqing key Laboratory of Micro Nano Structure Optoelectronics School of Physical Science and Technology Southwest University Chongqing400715 China

Solar photocatalytic hydrogen production is considered a promising technology owing to its sustainable nature, while facing the challenges of improving and maintaining photocatalytic efficiency under prolonged variable weather conditions. Herein, we screen out the MoTe2/ZrS2 system with a theoretical solar-to-hydrogen conversion efficiency of 10.37%. To improve the actual efficiency among all 97,711 grid cells in China, we propose an original meteorological data-driven machine learning model to optimize photocatalytic H2 production and results show that the annual average STH efficiency gives a mean of 3.16% within a range of 0.44% – 4.91% . Incorporating geospatial data, we determine that China's photocatalytic H2 potential is about 216.65 Mt/year, which has been improved by almost sixfold compared to that without optimization, and the country’s 2060 hydrogen demand can be met by using 11.08% of its total land area. Compared with photovoltaic electrolysis, a photocatalyst cost of 23 USD/m2cat/103hrs would make photocatalysis economically competitive. Last, considering hydrogen production fluctuations, we explore optimal operation of hydrogen storage and utilization facilities to fulfil downstream demands. © 2024, The Authors. All rights reserved.

关键词： Hydrogen production

来源：评论

学校读者我要写书评

暂无评论

Correlations between polarization and structural information of supertetragonal PbTiO3

引用

Physical Review B 2022年第2期105卷 024106-024106页

作者： Feng Zhang Jiale Zhang Hongmei Jing Zhipeng Li Dawei Wang Chun-Lin Jia School of Microelectronics and State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi'an 710049 China Key Lab of Micro-Nano Electronics and System Integration of Xi'an City Xi'an Jiaotong University Xi'an 710049 China School of Physics and Information Technology Shaanxi Normal University Xi'an 710062 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Ernst Ruska Center for Microscopy and Spectroscopy with Electrons Research Center Jülich D-52425 Jülich Germany

The huge axial ratio of supertetragonal perovskites can induce large polarization due to the coupling between the unit cell and ion displacements, which often results in higher Curie temperature or better ferroelectric properties. With the progress of vertical strain engineering, experimentally available supertetragonal PbTiO3 raises much interest in the relation between its intrinsic polarization and structural characteristics, such as the axial ratio and ion displacements that can be obtained with a high-resolution (scanning) transmission electron microscope nowadays. However, the interpretation and use of such obtained structural information are not without peril. Here, employing first-principles calculations, we report on the relationship between the polarization and the structural information for supertetragonal PbTiO3. Our investigation shows that, unlike normal PbTiO3, the strong sublinear correlation raises the difficulty to quantitatively estimate the spontaneous polarization for the axial ratio larger than 1.15. In addition, the relative displacement between cations (i.e., Pb and Ti) proves to be an unsuitable structural parameter to determine the spontaneous polarization, emphasizing the importance of obtaining the positions of anions, albeit presumably more difficult, along with cations.

关键词： Ferroelectricity Ferroelectrics Perovskites Density functional calculations First-principles calculations Scanning transmission electron microscopy Strain engineering

来源：评论

学校读者我要写书评

暂无评论

Tunable quantum interference effects in Floquet two- and three-level systems

arXiv

引用

arXiv 2022年

作者： Han, Yingying Qiao, Minchen Luo, Xiao-Qing Li, Tie-Fu Zhang, Wenxian Deng, Xiu-Hao You, J.Q. Yu, Dapeng Shenzhen Institute for Quantum Science and Engineering Southern University of Science and Technology Shenzhen518055 China Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology Center for Advanced Material Diagnostic Technology College of Engineering Physics Shenzhen Technology University Shenzhen518118 China Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education School of Physics and Technology Wuhan University Hubei Wuhan430072 China School of Integrated Circuits Tsinghua University Beijing100084 China Hunan Province Key Laboratory for Ultra-Fast Micro/Nano Technology and Advanced Laser Manufacture School of Electrical Engineering University of South China Hengyang421001 China School of Integrated Circuits and Frontier Science Center for Quantum Information Tsinghua University Beijing100084 China Beijing Academy of Quantum Information Sciences Beijing100193 China Guangdong Provincial Key Laboratory of Quantum Science and Engineering Southern University of Science and Technology Shenzhen518055 China Interdisciplinary Center of Quantum Information State Key Laboratory of Modern Optical Instrumentation Zhejiang Province Key Laboratory of Quantum Technology and Device Department of Physics Zhejiang University Hangzhou310027 China

Quantum interference effects in the un-modulated quantum systems with light-matter interaction have been widely studied, such as electromagnetically induced transparency (EIT) and Autler-Townes splitting (ATS). However, the similar quantum interference effects in the Floquet systems (i.e., periodically modulated systems), which might cover rich new physics, were rarely studied. In this article, we investigate the quantum interference effects in the Floquet two- and three-level systems analytically and numerically. We show a coherent destruction tunneling effect in a lotus-like multi-peak spectrum with a Floquet two-level system, where the intensity of the probe field is periodically modulated with a square-wave sequence. We demonstrate that the multi-peak split into multiple transparency windows with tunable quantum interference if the Floquet system is asynchronously controlled via a third level. Based on phenomenological analysis with Akaike information criterion, we show that the symmetric central transparency window has a similar mechanism to the traditional ATS or EIT depending on the choice of parameters, additional with an extra degree of freedom to control the quantum interference provided by the modulation period. The other transparent windows are shown to be asymmetric, different from the traditional ATS/EIT windows. These non-trivial quantum interference effects open up a new scope to explore the applications of the Floquet systems. © 2022, CC BY.

关键词： Transparency

来源：评论

学校读者我要写书评

暂无评论

Strong Neel ordering and luminescence correlation in a two-dimensional antiferromagnet

arXiv

引用

arXiv 2022年

作者： Zhou, Yongheng He, Kaiyue Hu, Huamin Ouyang, Gang Zhu, Chao Wang, Wei Qin, Sichen Tao, Ye Chen, Runfeng Zhang, Le Shi, Run Cheng, Chun Wang, Han Liu, Yanjun Liu, Zheng Wang, Taihong Huang, Wei Wang, Lin Chen, Xiaolong Department of Electrical and Electronic Engineering Southern University of Science and Technology Shenzhen518055 China 30 South Puzhu Road Nanjing211816 China Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Key Laboratory for Matter Microstructure and Function of Hunan Province Hunan Normal University Changsha410081 China SEU-FEI Nano-Pico Center Key Laboratory of MEMS of Ministry of Education Collaborative Innovation Center for Micro/Nano Fabrication Device and System Southeast University Nanjing210096 China School of Materials Science and Engineering Nanyang Technological University Singapore639798 Singapore 127 West Youyi Road Xi'An710072 China Nanjing University of Posts & Telecommunications 9 Wenyuan Road Nanjing210023 China Department of Materials Science and Engineering Southern University of Science and Technology Shenzhen518055 China

Magneto-optical effect has been widely used in light modulation, optical sensing and information storage. Recently discovered two-dimensional (2D) van der Waals layered magnets are considered as promising platforms for investigating novel magneto-optical phenomena and devices, due to the long-range magnetic ordering down to atomically-thin thickness, rich species and tunable properties. However, majority 2D antiferromagnets suffer from low luminescence efficiency which hinders their magneto-optical investigations and applications. Here, we uncover strong light-magnetic ordering interactions in 2D antiferromagnetic MnPS3 utilizing a newly-emerged near-infrared photoluminescence (PL) mode far below its intrinsic bandgap. This ingap PL mode shows strong correlation with the Neel ordering and persists down to monolayer thickness. Combining the DFT, STEM and XPS, we illustrate the origin of the PL mode and its correlation with Neel ordering, which can be attributed to the oxygen ion-mediated states. Moreover, the PL strength can be further tuned and enhanced using ultraviolet-ozone treatment. Our studies offer an effective approach to investigate light-magnetic ordering interactions in 2D antiferromagnetic semiconductors. © 2022, CC BY-NC-SA.

关键词： Manganese compounds

来源：评论

学校读者我要写书评

暂无评论

A Practical and High-Performance Nitrogen Dioxide Gas Sensor that Can Be Rapidly Mass-Produced Based on Gallium Nitride Quantum Dots Film

SSRN

引用

SSRN 2022年

作者： Han, Dan Chen, Yi Li, Donghui Dong, Hailiang Xu, Bingshe Sang, Shengbo He, Xiuli Shanxi Key Laboratory of Micro Nano Sensors & Artificial Intelligence Perception College of Information and Computer Taiyuan University of Technology Taiyuan030024 China Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan030024 China Key Laboratory of Interface Science and Engineering in Advanced Materials Taiyuan University of Technology Ministry of Education Taiyuan030024 China State Key Laboratory of Transducer Technology Aerospace Information Research Institute Chinese Academy of Sciences Beijing100190 China Shanxi Research Institute of 6D Artificiat Intelligence Biomedical Science Taiyuan030024 China

Gallium nitride (GaN) has some challenges for gas sensing, such as high detection lower limit (LOD) or controlling the epitaxy of nanostructures. To address these issues, we exclusively designed a device to enhance the gas interaction capabilities of GaN quantum dots (QDs) film fabricated by metal-organic chemical vapor deposition (MOCVD). The GaN QDs film gas sensor exhibited a low LOD (5 ppb) to NO2 at room temperature (RT), which has much superior gas performance than other GaN-based sensors. The results manifest that many ultra-small QDs around 2 nm in diameter are stacked to form QDs of larger size, and confirm the existence of vacancies. The sensor displays a ultra-high electron mobility of 1237.37 cm2 V−1s−1, demonstrate that great shallow donor impurities in GaN QDs film that ionize easily at RT, which is greatly beneficial for gas sensing. The sensing mechanisms were analyzed based on its abundant active sites, ultrahigh carrier mobility, high surface energy and chemical activity, grain boundary barrier and good electrical conductivity. Moreover, the sensor processes high selectivity, repeatability, stability and reusability based on MOCVD technology which can realize precise control of structure, morphology and surface energy level, which is expected to achieve rapid industrialization. © 2022, The Authors. All rights reserved.

关键词： Gallium nitride

来源：评论

学校读者我要写书评

暂无评论

Structural phase transition of monochalcogenides investigated with machine learning

引用

Physical Review B 2022年第9期105卷 094116-094116页

作者： J. Zhang F. Zhang D. Wei L. Liu X. Liu D. Fang G. X. Zhang X. Chen D. Wang School of Microelectronics & State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi'an 710049 China Key Lab of Micro-Nano Electronics and System Integration of Xi'an City Xi'an Jiaotong University Xi'an 710049 China Guangxi Key Laboratory of Optical and Electronic Materials and Devices College of Materials Science and Engineering Guilin University of Technology Guilin 541004 China Engineering Research Center of Nanoelectronic Integration and Advanced Equipment Ministry of Education School of Physics and Electronic Science East China Normal University Shanghai 200062 China MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter School of Physics Xi' an Jiaotong University Xi'an 710049 China School of Chemistry and Chemical Engineering Harbin Institute of Technology Harbin 150001 China Department of Applied Physics Aalto University Espoo 00076 Finland

As machine learning becomes increasingly important in science and engineering, it holds the promise to provide a universal approach applicable to various systems to investigate their crystalline phase transitions. Here, we build and train accurate artificial neural networks that can distinguish tiny energy difference, which is crucial to predict the crystalline phase transitions. Employing the trained artificial neural networks in Monte Carlo simulations as the surrogate energy function, we apply this approach to monochalcogenides, including bulk and two-dimensional monolayer SnTe and GeTe, investigating their crystalline phase transitions. The machine-learning approach, when viewed as providing a universal mathematical structure, can be transferred to the investigation of other materials when the training data set generated with ab initio methods are available. Moreover, the machine-learning approach resolves the difficulties associated with constructing the effective Hamiltonian for monochalcogenides, showing great potential with its accuracy and efficiency.

关键词： Ferroelectricity Structural phase transition Chalcogenides Machine learning

来源：评论

学校读者我要写书评

暂无评论

Phyllotaxis-inspired nanosieves with multiplexed orbital angular momentum

引用

eLight 2021年第1期1卷 46-56页

作者： Zhongwei Jin David Janoschka Junhong Deng Lin Ge Pascal Dreher Bettina Frank Guangwei Hu Jincheng Ni Yuanjie Yang Jing Li Changyuan Yu Dangyuan Lei Guixin Li Shumin Xiao Shengtao Mei Harald Giessen Frank Meyer zu Heringdorf Cheng-Wei Qiu Department of Electrical and Computer Engineering National University of Singapore4 Engineering Drive 3Singapore 117583Singapore College of Optical and Electronic Technology China Jiliang UniversityHangzhou 310018China Faculty of Physics and Center for Nanointegration Duisburg-Essen(CENIDE) University of Duisburg-EssenLotharstrasse 1-2147057 DuisburgGermany Department of Materials Science and Engineering Shenzhen Institute for Quantum Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China Beijing Qianjunyide Technology Co.Ltd Beijing 100031China. Physics Institute and Stuttgart Center of Photonics Engineering(SCoPE) University of Stuttgart70569 Stutt-gartGermany. School of Physics University of ElectronicScience and Technology of ChinaChengdu 611731China. Key Laboratory of Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China. Department of Electronic and Information Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARChina. Department of Materials Science and Engineering City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong SARChina. State Key Laboratory On Tunable Laser Technology Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information SystemShenzhen Graduate SchoolHarbin Institute of TechnologyShenzhen 518055China.

nanophotonic platforms such as metasurfaces,achieving arbitrary phase profiles within ultrathin thickness,emerge as miniaturized,ultracompact and kaleidoscopic optical vortex ***,it is often required to segment or interleave independent sub-array metasurfaces to multiplex optical vortices in a single nano-device,which in turn affects the device’s compactness and channel ***,inspired by phyllotaxis patterns in pine cones and sunflowers,we theoretically prove and experimentally report that multiple optical vortices can be produced in a single compact phyllotaxis nanosieve,both in free space and on a chip,where one meta-atom may contribute to many vortices *** time-resolved dynamics of on-chip interference wavefronts between multiple plasmonic vortices was revealed by ultrafast time-resolved photoemission electron *** nature-inspired optical vortex generator would facilitate various vortex-related optical applications,including structured wavefront shaping,free-space and plasmonic vortices,and high-capacity information metaphotonics.

关键词： Phyllotaxis vortex nanosieve Free-space Plasmonic vortices Ultrafast time-resolved

来源：评论

学校读者我要写书评

暂无评论

A Superhydrophobic Chip Integrated with an Array of Medium Reservoirs for Long-Term Hanging Drop Spheroid Culture

SSRN

引用

SSRN 2021年

作者： Sun, Bangyong Zhao, Yi Wu, Weimin Zhao, Qiang Li, Gang Key Laboratory of Optoelectronic Technology and Systems Ministry of Education Defence Key Disciplines Lab of Novel Micro-Nano Devices and System Technology Chongqing University Chongqing400044 China Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment Chongqing University Cancer Hospital Chongqing400030 China School of Mechanical and Power Engineering Chongqing University of Science and Technology Chongqing401331 China

Hanging drop (HD) is one of the most popular methods used for forming three-dimensional (3D) cell spheroids. However, conventional hanging drop systems are only applicable for short-term spheroid culture due to their inconvenience in exchanging cell culture media. Here we present a medium-reservoir-integrated superhydrophobic (MRI-SH) chip for long-term HD spheroid cultures. The device consists of two main components: i) a patterned superhydrophobic (SH) surface containing an array of wettable spots which anchor arrays of droplets of cell suspension, and ii) an array of chambers that serve as medium reservoirs, both interconnected via an array of thru-holes. This configuration provides two distinct advantages over conventional HD configurations: i) the high wettability contrast of the SH pattern on the chip leads to the formation and adhesion of nearly spherical hanging droplets on its surface, which minimizes interactions between the liquid and the substrate;ii) the integrated chambers provide large volumes of medium to maintain longer culture durations. Using this device, spheroids of MHCC97H cells were successfully formed, and the cultured spheroids could maintain high viability for up to 30 days and exhibited enhanced spheroid morphology compared to those cultured in the conventional HD systems. © 2021, The Authors. All rights reserved.

关键词： Drops

来源：评论

学校读者我要写书评

暂无评论

Towards ultrafast cooling through transient phonon currents: A closed-form solution

引用

Physical Review B 2021年第7期103卷 075427-075427页

作者： Xiaobin Chen Jiangtao Yuan Jian Wang School of Science State Key Laboratory on Tunable laser Technology and Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System Harbin Institute of Technology Shenzhen Shenzhen 518055 China Collaborative Innovation Center of Extreme Optics Shanxi University Taiyuan 030006 China Department of Physics and the Center of Theoretical and Computational Physics The University of Hong Kong Hong Kong China College of Physics and Optoelectronic Engineering Shenzhen University Shenzhen 518060 China

We develop a closed-form formula to calculate the transient thermal currents flowing through an arbitrary nanoscale phonon device in response to a sudden thermal switch. Our theory provides a solution to the problem in the far-from-equilibrium nonlinear response regime beyond the wide-band-like approximation and Drude regularization. We present calculations in a one-dimensional monatomic chain with Lorentzian-like thermal baths and show that the transient phonon currents are significantly larger than the long-time-limit steady-state phonon current. From the formula's clear mathematical structure, we also show that the transient oscillation periodicity and relaxation time are determined by the poles of the retarded phonon Green's function. In addition, higher temperatures of the thermal baths and stronger coupling between the baths and the central monatomic chain result in higher transient thermal currents. Our results suggest that ultrafast cooling of nanodevices through transient phonon currents is a promising route.

关键词： Ballistic transport Phonons Quantum transport Nonequilibrium Green's function

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：