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Efficient Extraction of Hot Carriers in Perovskite Quantum Dot through Building State Coupled Complex

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arXiv 2022年

作者： Li, Yusheng Jiang, Junke Wang, Dandan Liu, Dong Yajima, Shota Li, Hua Fuchimoto, Akihito Li, Hongshi Shi, Guozheng Hayase, Shuzi Tao, Shuxia Shi, Jiangjian Meng, Qingbo Ding, Chao Shen, Qing Faculty of Informatics and Engineering The University of Electro-Communications 1-5-1 Chofugaoka Chofu Tokyo182-8585 Japan Materials Simulation and Modelling Department of Applied Physics Eindhoven University of Technology Eindhoven5600 MB Netherlands Institute of New Energy Materials Chemistry School of Materials Science and Engineering Nankai University TongYan street 38 Jinnan District Tianjin300350 China 4-1-8 Honcho Saitama Kawaguchi332-0012 Japan Key Laboratory for Renewable Energy Beijing Key Laboratory for New Energy Materials and Devices Institute of Physics Chinese Academy of Sciences Beijing100190 China

Utilizing hot carriers is the crucial approach for solar cell to exceed the thermodynamic detailed balance limit, yet effective extraction of hot carriers in absorber materials via most commonly used semiconductor acceptors has been a challenge in both materials and photophysics research for many years. Herein, we build series of CsPbI3 quantum dot and fullerene derivative systems to explore the decisive factors of this process and have for the first time realized efficient hot carrier extraction in these systems (maximum extraction efficiency ~ 84%). We find building the systems as state-coupled complexes creates new carrier transport channels at about 0.22 eV above CsPbI3 quantum dot bandgap, which facilitates highly efficient HC extraction. Our research directly visualizes the inner connection of molecule interaction and ultrafast hot carrier extraction. The knowledge and strategy gained here are of universal meaning, taking an important step forward true hot carrier photovoltaics. Copyright © 2022, The Authors. All rights reserved.

关键词： Extraction

A U-Net-Based Self-Stitching Method for Generating Periodic Grain Structures

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arXiv 2023年

作者： Ji, Ye Koeppe, Arnd Altschuh, Patrick Griem, Lars Rajagopal, Deepalaxmi Nestler, Britta Chen, Weijin Zhang, Yi Zheng, Yue Centre for Physical mechanics and Biophysics School of Physics Sun Yat-Sen University Xin’gang West Road 135 Guangdong Guangzhou510275 China Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices School of Physics Xin’gang West Road 135 Guangdong Guangzhou510275 China State Key Laboratory of Optoelectronic Materials and Technologies School of Physics Xin’gang West Road 135 Guangdong Guangzhou510275 China Institute for Applied Materials–Microstructure Modelling and Simulation Karlsruhe Institute of Technology Strasse am Forum 7 Baden-Württemberg Karlsruhe76131 Germany Institute for Digital Materials Science Karlsruhe University of Applied Sciences Moltkestr. 30 Baden-Württemberg Karlsruhe76133 Germany

When modeling microstructures, the computational resource requirements increase rapidly as the simulation domain becomes larger. As a result, simulating a small representative fraction under periodic boundary conditions is often a necessary simplification. However, the truncated structures leave nonphysical boundaries, which are detrimental to numerical modeling. Here, we propose a self-stitching algorithm for generating periodic structures, demonstrated in a grain structure. The main idea of our algorithm is to artificially add structural information between mismatched boundary pairs, using the hierarchical spatial predictions of the U-Net. The algorithm provides an automatic and unbiased way to obtain periodic boundaries in grain structures and can be applied to porous microstructures in a similar way. Copyright © 2023, The Authors. All rights reserved.

关键词： Periodic structures

Realization of inverse-design magnonic logic gates

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science Advances 2025年第21期11卷 eadu9032页

作者： Zenbaa, Noura Majcen, Fabian Abert, Claas Bruckner, Florian Mauser, Norbert J. Schrefl, Thomas Wang, Qi Suess, Dieter Chumak, Andrii V. Faculty of Physics University of Vienna Vienna1090 Austria Vienna Doctoral School in Physics University of Vienna Vienna1090 Austria Research Platform MMM"Mathematics-Magnetism-Materials" University of Vienna Vienna1090 Austria Faculty of Mathematics University of Vienna Vienna1090 Austria Center for Modelling and Simulation Universität für Weiterbildung Krems Wiener Neustadt2700 Austria School of Physics Hubei Key Laboratory of Gravitation and Quantum Physics Institute for Quantum Science and Engineering Huazhong University of Science and Technology Wuhan430074 China

Magnonic logic gates represent a crucial step toward realizing fully magnonic data processing systems without reliance on conventional electronic or photonic elements. Recently, a universal and reconfigurable inverse-design device has been developed, featuring a 7 by 7 array of independent current loops that create local inhomogeneous magnetic fields to scatter spin waves in an yttrium-iron-garnet film. Although initially used for linear radio frequency components, we now demonstrate key nonlinear logic gates, NOT, OR, NOR, AND, NAND, and a half-adder, sufficient for building a full processor. In this system, binary data ("0"and"1") are encoded in the spin-wave amplitude. The contrast ratio, representing the difference between logic states, achieved values of 34, 53.9, 11.8, 19.7, 17, and 9.8 decibels for these gates, respectively. Copyright © 2025 The Authors, some rights reserved.

关键词： Logic gates

Characterization of Electronic Properties, Exchange Splitting and Ferromagnetic Arrangement in New Ti-Doped BaO

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Research Square

Research Square 2020年

作者： Hachemaoui, Malika Meskine, Mohamed Mokaddem, Allel Doumi, Bendouma Mogulkoc, Yesim Tadjer, Abdelkader Faculty of Sciences Department of Physics University of Saida Dr. Moulay Tahar Saida20000 Algeria Instrumentation and Advanced Materials Laboratory University Center of Nour Bachir El-Bayadh El-Bayadh 32000 Algeria University Center of Nour Bachir El-Bayadh El-Bayadh 32000 Algeria Department of Engineering Physics Ankara University Tandogan Ankara 06100 Turkey Modelling and Simulation in Materials Science Laboratory Physics Department Djillali Liabes University of Sidi Bel-Abbes Sidi Bel-Abbes22000 Algeria

We have studied the electronic structures, ferromagnetic properties, half-metallicity and exchange splitting in BaO doped with titanium such as Ba1-xTixO at concentration x = 0.125. The structural parameters of BaO and Ba0.875Ti0.125O compounds are calculated with generalised gradient approximation of Wu and Cohen, while their electronic structures, accurate band gaps and magnetic properties are evaluated by the use of the Tran-Blaha-modified Becke-Johnson potential. The changes of lattice parameter and bulk modulus of Ba0.875Ti0.125O are discussed with respect to the BaO. We have found that the Ba0.875Ti0.125O has a wide half-metallic ferromagnetic gap of 2.701 eV and a half-metallic gap of 0.803 eV with integral Bohr magneton of 2 μB, where its ferromagnetic state is characterised by the main contribution of the direct exchange splitting. Therefore, the Ba0.875Ti0.125O is true half-metallic ferromagnet with spin polarisation of 100 % and appears to be promising material for spintronics applications. © 2020, CC BY.

关键词： Electronic structure

Theoretical study of intermolecular interactions in protic ionic liquids: a single ion pair picture

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Journal of Physics: Conference Series 2021年第1期1719卷

作者： P Nanthanasit N Chattrapiban M Jitvisate P Nimmanpipug S Rimjaem Ph.D. Degree Program in Physics (International Program) Department of Physics and Materials Science Faculty of Science Chiang Mai University Chiang Mai 50200 Thailand Plasma and Beam Physics Research Facility Department of Physics and Materials Science Faculty of Science Chiang Mai University Chiang Mai 50200 Thailand Thailand Center of Excellence in Physics Ministry of Higher Education Science Research and Innovation Bangkok 10400 Thailand The Establishment of Research Center for Quantum Technology Faculty of Science Chiang Mai University Chiang Mai 50200 Thailand Computational Simulation and Modelling Laboratory Faculty of Science and Center of Excellence for Innovation in Analytical Science and Technology Chiang Mai University Chiang Mai 50200 Thailand

Protic ionic liquids are made via intermolecular transfer between cation and anion. This research employs theoretical calculation to gain understanding of the intermolecular interactions at single-ion-pair level and their consequences to the macroscopic properties of the ionic liquids. The protic ionic liquids used in this study are ethylammonium nitrate (EAN), propylammonium nitrate (PAN), and butylammonium nitrate (BAN). Molecular structures of ions and ion pair of each liquid are optimized using the density functional theory. The ion pair binding energies and infrared spectra of optimized structures are investigated. Infrared spectra of separated cation and anion are compared with cation-anion ion pair to specify the vibrational band shifts due to intermolecular interactions. The infrared-spectra show the hydrogen-bond stretching modes in the far-infrared region at the wavenumber between 108-252 cm−1 and the red shifts of four vibrational bands due to intermolecular interactions between the ions. Three vibrational band shifts are mainly due to Coulomb force, and the other shift is caused by combination of intermolecular interactions. Moreover, the energy calculations show that the binding energy decreases as the alkyl chain length increases.

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Using data-reduction techniques to analyse biomolecular trajectories

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arXiv 2019年

作者： Tribello, Gareth A. Gasparotto, Piero Atomistic Simulation Centre School of Mathematics and Physics Queen’s University Belfast BelfastBT7 1NN United Kingdom Laboratory of Computational Science and Modelling National Centre for Computational Design and Discovery of Novel Materials MARVEL IMX École Polytechnique Fédérale de Lausanne Lausanne1015 Switzerland

This chapter discusses the way in which dimensionality reduction algorithms such as diffusion maps and sketch-map can be used to analyze molecular dynamics trajectories. The first part discusses how these various algorithms function as well as practical issues such as landmark selection and how these algorithms can be used when the data to be analyzed comes from enhanced sampling trajectories. In the later parts a comparison between the results obtained by applying various algorithms to two sets of sample data are performed and Copyright © 2019, The Authors. All rights reserved.

关键词： Trajectories

Effects of surface vibrations on interlayer mass transport: Ab initio molecular dynamics investigation of Ti adatom descent pathways and rates from TiN/TiN(001) islands

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Physical Review B 2018年第3期97卷 035406-035406页

作者： D. G. Sangiovanni A. B. Mei D. Edström L. Hultman V. Chirita I. Petrov J. E. Greene Atomistic Modelling and Simulation Interdisciplinary Centre for Advanced Materials Simulation (ICAMS) Ruhr-Universität Bochum D-44801 Bochum Germany Thin Film Physics Division Department of Physics Chemistry and Biology (IFM) Linköping University SE-58183 Linköping Sweden Departments of Materials Science Physics and the Frederick Seitz Materials Research Laboratory University of Illinois Urbana Illinois 61801 USA Department of Materials Science and Engineering Cornell University Ithaca New York 14853 USA

We carried out density-functional ab initio molecular dynamics (AIMD) simulations of Ti adatom (Tiad) migration on, and descent from, square TiN〈100〉 epitaxial islands on TiN(001) at temperatures (T) ranging from 1200 to 2400 K. Adatom-descent energy barriers determined via ab initio nudged-elastic-band calculations at 0 Kelvin suggest that Ti interlayer transport on TiN(001) occurs essentially exclusively via direct hopping onto a lower layer. However, AIMD simulations reveal comparable rates for Tiad descent via direct hopping vs push-out/exchange with a Ti island-edge atom for T≥1500K. We demonstrate that this effect is due to surface vibrations, which yield considerably lower activation energies at finite temperatures by significantly modifying the adatom push-out/exchange reaction pathway.

关键词： Adsorption Crystal growth Island Lattice dynamics Surface diffusion Ceramics Nitrides Transition metals Density functional calculations Molecular dynamics

Phonon and electron contributions to the thermal conductivity of VNx epitaxial layers

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Physical Review materials 2017年第6期1卷 065002-065002页

作者： Qiye Zheng Antonio B. Mei Mohit Tuteja Davide G. Sangiovanni Lars Hultman Ivan Petrov J. E. Greene David G. Cahill Department of Materials Science and Engineering Frederick Seitz Materials Research Laboratory University of Illinois at Urbana-Champaign 104 South Goodwin Urbana Illinois 61801 USA Atomistic Modelling and Simulation ICAMS Ruhr-Universität Bochum D-44801 Bochum Germany Department of Physics (IFM) Linköping University SE-581 83 Linköping Sweden

Thermal conductivities of VNx/MgO(001) (0.76≤x≤1.00) epitaxial layers, grown by reactive magnetron sputter deposition, are measured in the temperature range 300<T<1000K using time-domain thermoreflectance (TDT... 详细信息

Thermal conductivities of VNx/MgO(001) (0.76≤x≤1.00) epitaxial layers, grown by reactive magnetron sputter deposition, are measured in the temperature range 300

关键词： Elastic modulus Electrical conductivity Electron thermal conductivity Lattice thermal conductivity Metals Thermal conductivity Thin films Boltzmann theory Crystal structures Drude model Epitaxy Laser techniques Resistivity measurements Rutherford back scattering spectroscopy Sputtering Thermoreflectance X-ray diffraction

Effects of surface vibrations on interlayer mass-transport: ab initio molecular dynamics investigation of Ti adatom descent pathways and rates from TiN/TiN(001) islands

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arXiv 2017年

作者： Sangiovanni, D.G. Mei, A.B. Edström, D. Hultman, L. Chirita, V. Petrov, I. Greene, J.E. Atomistic Modelling and Simulation ICAMS Ruhr-Universität Bochum BochumD-44801 Germany Linköping University LinköpingSE-58183 Sweden Departments of Materials Science Physics Frederick Seitz Materials Research Laboratory University of Illinois UrbanaIL61801 United States Department of Materials Science and Engineering Cornell University IthacaNY14853 United States

We carry out density-functional ab initio molecular dynamics (AIMD) simulations of Ti adatom (Tiad) migration on, and descent from, TiN -faceted epitaxial islands on TiN(001) at temperatures T ranging from 1200 to 2400 K. Adatom-descent energy-barriers determined via ab initio nudged-elastic-band calculations at 0 Kelvin suggest that Ti interlayer transport on TiN(001) occurs essentially exclusively via direct hopping onto a lower layer. However, AIMD simulations reveal comparable rates for Tiad descent via direct-hopping vs. push-out/exchange with a Ti island edge atom for T ≥ 1500 K. We demonstrate that the effect is due to surface vibrations, which yield considerably lower activation energies at finite temperatures by significantly modifying the adatom push/out-exchange reaction pathway. Copyright © 2017, The Authors. All rights reserved.

关键词： Adatoms