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Peptoid-Directed Formation of Five-Fold Twinned Au Nanostars through Particle Attachment and Facet Stabilization

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Angewandte Chemie 2022年第14期134卷

作者： Dr. Biao Jin Dr. Feng Yan Dr. Xin Qi Dr. Bin Cai Dr. Jinhui Tao Dr. Xiaofeng Fu Dr. Susheng Tan Dr. Peijun Zhang Dr. Jim Pfaendtner Nada Y. Naser Dr. François Baneyx Dr. Xin Zhang Dr. James J. DeYoreo Dr. Chun-Long Chen Physical Sciences Division Pacific Northwest National Laboratory 902 Battelle Boulevard Richland WA 99352 USA School of Chemistry & Chemical Engineering Linyi University The Middle Part of Shuangling Road Linyi Shandong Province 276005 China Department of Chemical Engineering University of Washington 1410 NE Campus Parkway Seattle WA 98195 USA Present address: School of Chemistry and Chemical Engineering Shandong University Shanda Nan Road 27 Jinan (China) Department of Biological Science Florida State University 600 W College Ave Tallahassee FL 32306 USA Department of Electrical and Computer Engineering & Petersen Institute of Nanoscience and Engineering (PINSE) University of Pittsburgh 4200 Fifth Ave Pittsburgh PA 15260 USA Division of Structural Biology Wellcome Trust Centre for Human Genetics University of Oxford Roosevelt Drive Wellington Square Oxford OX3 7BN UK Diamond Light Source Harwell Science and Innovation Campus Didcot OX11 0DE UK Department of Materials Science and Engineering University of Washington 1410 NE Campus Parkway Seattle WA 98195 USA

While bio-inspired synthesis offers great potential for controlling nucleation and growth of inorganic particles, precisely tuning biomolecule–particle interactions is a long-standing challenge. Herein, we used variations in peptoid sequence to manipulate peptoid–Au interactions, leading to the synthesis of concave five-fold twinned, five-pointed Au nanostars via a process of repeated particle attachment and facet stabilization. Ex situ and liquid-phase TEM observations show that a balance between particle attachment biased to occur near the star points, preferential growth along the [100] direction, and stabilization of (111) facets is critical to forming star-shaped particles. Molecular simulations predict that interaction strengths between peptoids and distinct Au facets differ significantly and thus can alter attachment kinetics and surface energies to form the stars. This work provides new insights into how sequence-defined ligands affect particle growth to regulate crystal morphology.

关键词： Facet Stabilization Five-Fold Twinned Au Star Particle Attachment Sequence-Defined Peptoids

Tungsten boride: a 2D multiple dirac semimetal for hydrogen evolution reaction

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arXiv 2019年

作者： Wang, Aizhu Shen, Lei Zhao, Mingwen Wang, Junru Li, Weifeng Zhou, Weijia Feng, Yuanping Liu, Hong Institute for Advanced Interdisciplinary Research University of Jinan JinanShandong250022 China Department of Electrical and Computer Engineering Department of Physics National University of Singapore Singapore117579 Singapore Department of Mechanical Engineering Engineering Science Programme Faculty of Engineering National University of Singapore Singapore117575 Singapore School of Physics State Key Laboratory of Crystal Materials Shandong University JinanShandong250100 China Department of Physics & Centre for Advanced Two-dimensional Materials National University of Singapore Singapore117542 Singapore State Key Laboratory of Crystal Materials Shandong University JinanShandong250100 China

Here, we propose a two-dimensional (2D) tungsten boride (WB4) lattice, with the Gibbs free energy for the adsorption of atomic hydrogen (ΔGH) tending to be the ideal value (0 eV) at 3% strained state, to host a better hydrogen evolution reaction (HER) activity. Based on first-principles calculations, it is demonstrated that the multiple d-p-π and d-p-σ Dirac conjugations of WB4 lattice ensures its excellent electronic transport characteristics. Meanwhile, coupling with the d-orbitals of W, the p-orbitals of borophene subunits in WB4 lattice can modulate the d band center to get a good HER performance. Our results not only provide a versatile platform for hosting multiple Dirac semimetal states with a "sandwich" configuration, but also offer a guiding principle for discovering the relationship between intrinsic properties of the active center and the catalytic activity of metal layer from the emerging field of 2D noble-metal-free lattices. Copyright © 2019, The Authors. All rights reserved.

关键词： Calculations

Unidirectional plasmonic edge modes on general two-dimensional materials

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arXiv 2019年

作者： Stauber, T. Nemilentsau, A. Low, T. Gómez-Santos, G. Materials Science Factory Instituto de Ciencias de Materiales de Madrid CSIC MadridE-28049 Spain Department of Electrical & Computer Engineering University of Minnesota MinneapolisMN55455 United States Universidad Autónoma de Madrid MadridE-28049 Spain

We investigate the field and spin-momentum coupling of edge plasmons hosted by general two-dimensional materials and identify sweet spots depending on the polarisation plane, ellipticity and the position of an electric dipole relative to the plane and edge. Exciting the dipole at these sweet spots by propagating light leads to uni-directional propagating edge plasmons or edge modes suppression. We also extend previous approximate treatments [A. Fetter Phys. Rev. B 32, 7676 (1985)] to include anisotropy and hyperbolic systems, elucidating its predictions for the existence of edge modes. A thorough assessment of the approximate description is carried out, comparing its spin-momentum coupling features in the near field with exact results from Wiener-Hopf techniques. Simulations are also performed confirming the overall picture. Our results shed new light on the quest of chiral plasmonics in 2D materials and should be relevant for future experiments. Copyright © 2019, The Authors. All rights reserved.

关键词： Plasmonics

Achieving a quantum smart workforce

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arXiv 2020年

作者： Aiello, Clarice D. Awschalom, D.D. Bernien, Hannes Brower-Thomas, Tina Brown, Kenneth R. Brun, Todd A. Caram, Justin R. Chitambar, Eric Di Felice, Rosa Fox, Michael F.J. Haas, Stephan Holleitner, Alexander W. Hudson, Eric R. Hunt, Jeffrey H. Joynt, Robert Koziol, Scott Lewandowski, H.J. McClure, Douglas T. Palsberg, Jens Passante, Gina Pudenz, Kristen L. Richardson, Christopher J.K. Rosenberg, Jessica L. Ross, R.S. Saffman, Mark Singh, M. Steuerman, David W. Stark, Chad Thijssen, Jos Vamivakas, A. Nick Whitfield, James D. Zwickl, Benjamin M. Department of Electrical and Computer Engineering University of California Los Angeles Los AngelesCA90095 United States Pritzker School of Molecular Engineering University of Chicago ChicagoIL60637 United States Department of Physics University of Chicago ChicagoIL60637 United States Center for Molecular Engineering and Materials Science Division Argonne National Laboratory LemontIL60439 United States Howard University Graduate School WashingtonDC20059 United States Center for Integrated Quantum Materials Howard University PI WashingtonDC20059 United States Departments of Electrical and Computer Engineering Chemistry and Physics Duke University DurhamNC27708 United States Department of Electrical and Computer Engineering University of Southern California Los AngelesCA90089 United States UCLA Department of Chemistry and Biochemistry Center for Quantum Science and Engineering University of California – Los Angeles Los AngelesCA90095 United States Department of Electrical and Computer Engineering University of Illinois Urbana-ChampaignIL61801 United States Department of Physics and Astronomy University of Southern California Los AngelesCA90089 United States JILA National Institute of Standards and Technology University of Colorado BoulderCO80309 United States Department of Physics University of Colorado BoulderCO80309 United States Department of Physics and Astronomy University of Southern California Los AngelesCA90089 United States Garching85748 Germany UCLA Center for Quantum Science and Engineering University of California – Los Angeles Los AngelesCA90095 United States Boeing Company El SegundoCA90245 United States Department of Physics University of Wisconsin-Madison MadisonWI53706 United States Department of Electrical and Computer Engineering Baylor University WacoTX76798 United States Department of Physics University of Colorado BoulderCO80309 United States IBM T.J. Watson Research Center Yorktown HeightsNY

Interest in building dedicated Quantum Information science and engineering (QISE) education programs has greatly expanded in recent years. These programs are inherently convergent, complex, often resource intensive and likely require collaboration with a broad variety of stakeholders. In order to address this combination of challenges, we have captured ideas from many members in the community. This manuscript not only addresses policy makers and funding agencies (both public and private and from the regional to the international level) but also contains needs identified by industry leaders and discusses the difficulties inherent in creating an inclusive QISE curriculum. We report on the status of eighteen post-secondary education programs in QISE and provide guidance for building new programs. Lastly, we encourage the development of a comprehensive strategic plan for quantum education and workforce development as a means to make the most of the ongoing substantial investments being made in QISE. Copyright © 2020, The Authors. All rights reserved.

关键词： Personnel

Tackling Disorder in γ-Ga2O3

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arXiv 2022年

作者： Ratcliff, Laura E. Oshima, Takayoshi Nippert, Felix Janzen, Benjamin M. Kluth, Elias Goldhahn, Rüdiger Feneberg, Martin Mazzolini, Piero Bierwagen, Oliver Wouters, Charlotte Nofal, Musbah Albrecht, Martin Swallow, Jack E.N. Jones, Leanne A.H. Thakur, Pardeep K. Lee, Tien-Lin Kalha, Curran Schlueter, Christoph Veal, Tim D. Varley, Joel B. Wagner, Markus R. Regoutz, Anna Department of Materials Imperial College London LondonSW7 2AZ United Kingdom Centre for Computational Chemistry School of Chemistry University of Bristol BristolBS8 1TS United Kingdom Department of Electrical and Electronic Engineering Saga University Saga840-8502 Japan Technische Universität Berlin Institute of Solid State Physics Hardenbergstrasse 36 Berlin10623 Germany Institut für Physik Otto-von-Guericke-Universität Magdeburg Universitätsplatz 2 Magdeburg39106 Germany Paul-Drude-Institut fur Festkörperelektronik Leibniz-Institut im Forschungsverbund Berlin e.V. Hausvogteiplatz 5-7 Berlin10117 Germany Department of Mathematical Physical and Computer Sciences University of Parma Viale delle Scienze 7/A Parma43124 Italy Paul-Drude-Institut für Festkörperelektronik Leibniz-Institut im Forschungsverbund Berlin e.V. Hausvogteiplatz 5-7 Berlin10117 Germany Leibniz-Institut fÃŒr Kristallzüchtung Max-Born-Str. 2 Berlin12489 Germany Department of Materials University of Oxford Parks Road OxfordOX1 3PH United Kingdom Stephenson Institute for Renewable Energy Department of Physics University of Liverpool LiverpoolL69 7ZF United Kingdom Diamond Light Source Ltd. Diamond House Harwell Science and Innovation Campus Didcot OX11 0DE United Kingdom Diamond Light Source Ltd. Harwell Science and Innovation Campus Didcot OX11 0DE United Kingdom Department of Chemistry University College London 20 Gordon Street LondonWC1H 0AJ United Kingdom Deutsches Elektronen-Synchrotron DESY Notkestrasse 85 Hamburg22607 Germany Lawrence Livermore National Laboratory LivermoreCA94550 United States

Ga2O3 and its polymorphs are attracting increasing attention. The rich structural space of polymorphic oxide systems such as Ga2O3 offers potential for electronic structure engineering, which is of particular interest for a range of applications, such as power electronics. γ-Ga2O3 presents a particular challenge across synthesis, characterisation, and theory due to its inherent disorder and resulting complex structure - electronic structure relationship. Here, density functional theory is used in combination with a machine learning approach to screen nearly one million potential structures, thereby developing a robust atomistic model of the γ-phase. Theoretical results are compared with surface and bulk sensitive soft and hard X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, spectroscopic ellipsometry, and photoluminescence excitation spectroscopy experiments representative of the occupied and unoccupied states of γ-Ga2O3. The first onset of strong absorption at room temperature is found at 5.1 eV from spectroscopic ellipsometry, which agrees well with the excitation maximum at 5.17 eV obtained by PLE spectroscopy, where the latter shifts to 5.33 eV at 5 K. This work presents a leap forward in the treatment of complex, disordered oxides and is a crucial step towards exploring how their electronic structure can be understood in terms of local coordination and overall structure. Copyright © 2022, The Authors. All rights reserved.

关键词： Density functional theory

Extended Drude Model for Intraband-Transition-Induced Optical Nonlinearity

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Physical Review Applied 2019年第6期11卷 064062-064062页

作者： Heng Wang Kang Du Chuhao Jiang Zhiqiang Yang Lixia Ren Wending Zhang Soo Jin Chua Ting Mei MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Conditions and Shaanxi Key Laboratory of Optical Information Technology School of Science Northwestern Polytechnical University Xi’an 710072 China Department of Electrical and Computer Engineering National University of Singapore 4 Engineering Drive 3 Singapore 117583 LEES Program Singapore-MIT Alliance for Research & Technology (SMART) 1 CREATE Way #10-01 CREATE Tower Singapore 138602

No existing model has completely explained the physics of the optical nonlinearity for epsilon-near-zero materials, which have recently emerged as candidates for design and fabrication of active nanophotonic devices. We propose to extend the Drude model by adopting a weighted electron effective mass, which takes into account the electron distribution in the nonparabolic conduction band. The extended Drude model is able to interpret the cause of the nonlinearity and provide a functional relationship between the refractive index and wavelength. Both the band nonparabolicity and the temperature-dependent mobility are responsible for the intraband-transition-induced optical nonlinearity. The spectrally resolved nonlinear refractive index and nonlinear susceptibilities are obtained from this model. The results can be applied to other transparent conducting oxides and will help in the design and modeling of spectral responses of nonlinear plasmonic devices.

关键词： Electronic transitions Nonlinear optical susceptibility Optoelectronics Plasmonics Ultrafast optics Thin films Free-electron model Ultrafast pump-probe spectroscopy

Chiral plasmons with twisted atomic bilayers

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arXiv 2020年

作者： Lin, Xiao Liu, Zifei Stauber, Tobias Gómez-Santos, Guillermo Gao, Fei Chen, Hongsheng Zhang, Baile Low, Tony Interdisciplinary Center for Quantum Information State Key Laboratory of Modern Optical Instrumentation ZJU-Hangzhou Global Science and Technology Innovation Center College of Information Science and Electronic Engineering Zhejiang University Hangzhou310027 China Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University Singapore637371 Singapore Materials Science Factory Instituto de Ciencia de Materiales de Madrid CSIC MadridE-28049 Spain Institute for Theoretical Physics University of Regensburg RegensburgD-93040 Germany Universidad Autónoma de Madrid MadridE-28049 Spain Centre for Disruptive Photonic Technologies NTU Singapore637371 Singapore Department of Electrical and Computer Engineering University of Minnesota MinneapolisMN55455 United States

Van der Waals heterostructures of atomically thin layers with rotational misalignments, such as twisted bilayer graphene, feature interesting structural moirésuperlattices. Due to the quantum coupling between the twisted atomic layers, light-matter interaction is inherently chiral;as such, they provide a promising platform for chiral plasmons in the extreme nanoscale. However, while the interlayer quantum coupling can be significant, its influence on chiral plasmons still remains elusive. Here we present the general solutions from full Maxwell equations of chiral plasmons in twisted atomic bilayers, with the consideration of interlayer quantum coupling. We find twisted atomic bilayers have a direct correspondence to the chiral metasurface, which simultaneously possesses chiral and magnetic surface conductivities, besides the common electric surface conductivity. In other words, the interlayer quantum coupling in twisted van der Waals heterostructures may facilitate the construction of various (e.g., bi-anisotropic) atomically-thin metasurfaces. Moreover, the chiral surface conductivity, determined by the interlayer quantum coupling, determines the existence of chiral plasmons and leads to a unique phase relationship (i.e., ±π/2 phase difference) between their TE and TM wave components. Importantly, such a unique phase relationship for chiral plasmons can be exploited to construct the missing longitudinal spin of plasmons, besides the common transverse spin of plasmons. Copyright © 2020, The Authors. All rights reserved.

关键词： Plasmons

Precision measurement of electron-electron scattering in GaAs/AlGaAs using transverse magnetic focusing

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arXiv 2019年

作者： Gupta, Adbhut Heremans, Jean J. Kataria, Gitansh Chandra, Mani Fallahi, Saeed Gardner, Geoffrey C. Manfra, Michael J. Department of Physics Virginia Tech BlacksburgVA24061 United States Bradley Department of Electrical and Computer Engineering Virginia Tech BlacksburgVA24061 United States Department of Materials Science and Engineering Rensselaer Polytechnic Institute TroyNY12180 United States Department of Physics and Astronomy Purdue University West LafayetteIN47907 United States Birck Nanotechnology Center Purdue University West LafayetteIN47907 United States Microsoft Quantum Purdue Purdue University West LafayetteIN47907 United States School of Electrical and Computer Engineering Purdue University West LafayetteIN47907 United States School of Materials Engineering Purdue University West LafayetteIN47907 United States

Electron-electron (e-e) interactions assume a cardinal role in solid-state physics. Quantifying the e-e scattering length is hence critical. In this paper we show that the mesoscopic phenomenon of transverse magnetic focusing (TMF) in two-dimensional electron systems forms a precise and sensitive technique to measure this length scale. Conversely we quantitatively demonstrate that e-e scattering is the predominant effect limiting TMF amplitudes in high-mobility materials. Using high-resolution kinetic simulations, we show that the TMF amplitude at a maximum decays exponentially as a function of the e-e scattering length, which leads to a ready approach to extract this length from the measured TMF amplitudes. The approach is applied to measure the temperature-dependent e-e scattering length in high-mobility GaAs/AlGaAs heterostructures. The simulations further reveal current vortices that accompany the cyclotron orbits - a collective phenomenon counterintuitive to the ballistic transport underlying a TMF setting. Copyright © 2019, The Authors. All rights reserved.

关键词： Gallium arsenide

Title: Observation of Bloch-Siegert Shift in an Atomically Thin Crystal

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Title: Observation of Bloch-Siegert Shift in an Atomically T...

2018 IEEE Photonics Society Summer Topicals Meeting Series, SUM 2018

作者： Sie, Edbert J. Lui, C.H. Lee, Yi-Hsien Fu, Liang Kong, Jing Gedik, Nuh Department of Physics Massachusetts Institute of Technology CambridgeMA02139 United States Department of Physics and Astronomy University of California RiversideCA92521 United States Materials Science and Engineering National Tsing-Hua University Hsinchu30013 Taiwan Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology CambridgeMA02139 United States Geballe Laboratory for Advanced Materials Stanford University StanfordCA94305 United States

ISBN: (纸本)9781538653432

Coherent light-matter interaction can be used to manipulate the energy levels of atoms, molecules and solids. When light with frequency ω is detuned away from a resonance ω0, repulsion between the photon-dressed (Floquet) states can lead to a shift of energy resonance. The dominant effect is the optical Stark shift (∝ 1/( ω0-ω)), but there is an additional contribution from the so-called Bloch-Siegert shift (∝ 1/( ω0 + ω)). Although it is common in atoms and molecules, the observation of Bloch-Siegert shift in solids has so far been limited only to artificial atoms since the shifts were small (2 under infrared optical driving by virtue of the strong light-matter interaction in this system. Moreover, we can disentangle the Bloch-Siegert shift entirely from the optical Stark shift, because the two effects are found to obey opposite selection rules at different valleys. By controlling the light helicity, we can confine the Bloch-Siegert shift to occur only at one valley, and the optical Stark shift at the other valley. Such a valley-exclusive Bloch-Siegert shift allows for enhanced control over the valleytronic properties in two-dimensional materials, and offers a new avenue to explore quantum optics in solids. © 2018 IEEE.

关键词： Molecules