Nano Letters Journal Impact Factor & Information

Publisher: American Chemical Society, American Chemical Society

Journal description

A central forum for scientists involved in nanoscale research, among a wide range of disciplines that include physical and materials chemistry, biotechnology, and applied physics. Nano Letters reports on fundamental research in all branches of the theory and practice of nanoscience and nanotechnology. It will provide rapid disclosure of the key elements of a study, publishing preliminary, experimental, and theoretical results on the physical, chemical, and biological phenomena, processes and applications of structures within the nanoscale range. Areas of interest include: Synthesis and processing of organic, inorganic, and hybrid nanosized materials by physical, chemical, and biological methods; Modeling and simulation of synthetic, assembly, and interaction processes; Characterization of unique size properties; Realization and application of novel nanostructures and nanodevices. This is the second letters journal launched by ACS, following the 1999 release of Organic Letters, and charged with the same mission: To rapidly communicate preliminary significant research results.

Current impact factor: 12.94

Impact Factor Rankings

2015 Impact Factor Available summer 2015
2013 / 2014 Impact Factor 12.94
2012 Impact Factor 13.025
2011 Impact Factor 13.198
2010 Impact Factor 12.186
2009 Impact Factor 9.991
2008 Impact Factor 10.371
2007 Impact Factor 9.627
2006 Impact Factor 9.96
2005 Impact Factor 9.847
2004 Impact Factor 8.449
2003 Impact Factor 6.144
2002 Impact Factor 5.033

Impact factor over time

Impact factor

Additional details

5-year impact 14.13
Cited half-life 4.40
Immediacy index 2.47
Eigenfactor 0.37
Article influence 5.19
Website Nano Letters website
Other titles Nano letters (Online), Nano letters
ISSN 1530-6992
OCLC 44445939
Material type Document, Periodical, Internet resource
Document type Internet Resource, Computer File, Journal / Magazine / Newspaper

Publisher details

American Chemical Society

  • Pre-print
    • Author cannot archive a pre-print version
  • Restrictions
    • Must obtain written permission from Editor
    • Must not violate ACS ethical Guidelines
  • Post-print
    • Author cannot archive a post-print version
  • Restrictions
    • If mandated by funding agency or employer/ institution
    • If mandated to deposit before 12 months, must obtain waiver from Institution/Funding agency or use AuthorChoice
    • 12 months embargo
  • Conditions
    • On author's personal website, pre-print servers, institutional website, institutional repositories or subject repositories
    • Non-Commercial
    • Must be accompanied by set statement (see policy)
    • Must link to publisher version
    • Publisher's version/PDF cannot be used
    • If mandated sooner than 12 months, must obtain waiver from Editors or use AuthorChoice
    • Reviewed on 07/08/2014
  • Classification
    ​ white

Publications in this journal

  • Chang-Hua Liu, You-Chia Chang, Seunghyun Lee, Yaozhong Zhang, Yafei Zhang, Theodore B Norris, Zhaohui Zhong
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    ABSTRACT: The photo-Dember effect arises from the asymmetric diffusivity of photoexcited electrons and holes, which creates a transient spatial charge distribution and hence the buildup of a voltage. Conventionally, a strong photo-Dember effect is only observed in semiconductors with a large asymmetry between the electron and hole mobilities, such as in GaAs or InAs, and is considered negligible in graphene due to its electron-hole symmetry. Here, we report the observation of a strong lateral photo-Dember effect induced by nonequilibrium hot carrier dynamics when exciting a graphene-metal interface with a femtosecond laser. Scanning photocurrent measurements reveal the extraction of photoexcited hot carriers is driven by the transient photo-Dember field, and the polarity of the photocurrent is determined by the device's mobility asymmetry. Furthermore, ultrafast pump-probe measurements indicate the magnitude of photocurrent is related to the hot carrier cooling rate. Our simulations also suggest that the lateral photo-Dember effect originates from graphene's 2D nature combined with its unique electrical and optical properties. Taken together, these results not only reveal a new ultrafast photocurrent generation mechanism in graphene but also suggest new types of terahertz sources based on 2D nanomaterials.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b01912
  • Yanming Sun, Haiyu Fang, Lujun Pan, Meng Han, Shen Xu, Xinwei Wang, Biao Xu, Yue Wu
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    ABSTRACT: Small molecules with functional groups can show different electron affinity and binding behavior on nanocrystal surface, which, in principle, could be used to alternate the electrical transport in self-assembled nanocrystal thin films. These small molecules can also serve for scattering the phonons to reduce the thermal conductivity. Here, we present our research on the thermoelectric characteristic of self-assembled silver telluride (Ag2Te) nanocrystal thin films which are fabricated by a layer-by-layer (LBL) dip-coating process. We perform investigations on the electrical conductivity and Seebeck coefficient on the Ag2Te nanocrystal thin films containing hydrazine, 1,2-ethanedithiol, and ethylenediamine between 300 K and 400 K. We also use photothermal (PT) technique to obtain the thermal conductivity of the films at room temperature and estimate the thermoelectric figure of merit (ZT). The experimental results suggest that the surface-bound small molecules could serve as a beneficial component to build nanocrystal-based thermoelectric devices operating at low temperature.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b00255
  • Alexander Dobrovolsky, Per O Å Persson, Supanee Sukrittanon, Yanjin Kuang, Charles W Tu, Weimin M Chen, Irina A Buyanova
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    ABSTRACT: III-V semiconductor nanowires (NWs) have gained significant interest as building blocks in novel nanoscale devices. The one-dimensional (1D) nanostructure architecture allows one to extend band structure engineering beyond quantum confinement effects by utilizing formation of different crystal phases that are thermodynamically unfavorable in bulk materials. It is therefore of crucial importance to understand the influence of variations in the NWs crystal structure on their fundamental physical properties. In this work we investigate effects of structural polytypism on the optical properties of gallium phosphide and GaP/GaNP core/shell NW structures by a correlative investigation on the structural and optical properties of individual NWs. The former is monitored by transmission electron microscopy, whereas the latter is studied via cathodoluminescence (CL) mapping. It is found that structural defects, such as rotational twins in zinc blende (ZB) GaNP, have detrimental effects on light emission intensity at low temperatures by promoting nonradiative recombination processes. On the other hand, formation of the wurtzite (WZ) phase does not notably affect the CL intensity neither in GaP nor in the GaNP alloy. This suggests that zone folding in WZ GaP does not enhance its radiative efficiency, consistent with theoretical predictions. We also show that the change in the lattice structure have negligible effects on the bandgap energies of the GaNP alloys, at least within the range of the investigated nitrogen compositions of <2%. Both WZ and ZB GaNP are found to have a significantly higher efficiency of radiative recombination as compared with that in parental GaP, promising for potential applications of GaNP NWs as efficient nanoscale light emitters within the desirable amber-red spectral range.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b01054
  • Martin Wölz, Christian Hauswald, Timur Flissikowski, Tobias Gotschke, Sergio Fernandez-Garrido, Oliver Brandt, H T Grahn, Lutz Geelhaar, Henning Riechert
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    ABSTRACT: Vertical GaN nanowires are grown in a self-induced way on a sputtered Ti film by plasma-assisted molecular beam epitaxy. Both in-situ electron diffraction and ex-situ ellipsometry show that Ti is converted to TiN upon exposure of the surface to the N plasma. The ellipsometric data, in addition, demonstrate this TiN film to be metallic. The diffraction data evidence that the GaN nanowires have a strict epitaxial relationship to this film. Photoluminescence spectroscopy of the GaN nanowires shows excitonic transitions virtually identical in spectral position, linewidth and decay time to those of state-of-the-art GaN nanowires grown on Si. Therefore, the crystalline quality of the GaN nanowires grown on metallic TiN and on Si is equivalent. The freedom to employ metallic substrates for the epitaxial growth of semiconductor nanowires in high structural quality may enable novel applications that benefit from the associated high thermal and electrical conductivity as well as optical reflectivity.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b00251
  • Si-Young Choi, Sung-Dae Kim, Minseok Choi, Hak-Sung Lee, Jungho Ryu, Naoya Shibata, Teruyasu Mizoguchi, Eita Tochigi, Takahisa Yamamoto, Suk-Joong L Kang, Yuichi Ikuhara
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    ABSTRACT: Atomic-scale defects strongly influence the electrical and optical properties of materials, and their impact can be more pronounced in localized dimensions. Here we directly demonstrate that strain triggers the formation of oxygen vacancies in complex oxides by examining the tilt boundary of SrTiO3 bicrystals. Through transmission electron microscopy and electron energy loss spectroscopy, we identify the strains along the tilt boundary and oxygen vacancies in the strain-imposed regions between dislocation cores. First-principles calculations support that strains, irrespective of its type and sign, lower the formation energy of oxygen vacancies, thereby enhancing the vacancy formation. Finally, current-voltage measurement confirms that such oxygen vacancies at the strained boundary result in the decrease of non-linearity of I-V curve as well as resistivity. Our results strongly point that oxygen vacancies are preferentially formed, segregated at the region where strains accumulate, such as heterogeneous interfaces as well as at grain boundaries.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b01245
  • Taiyang Zhang, Mengjin Yang, Yixin Zhao, Kai Zhu
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    ABSTRACT: We demonstrate a facile morphology-controllable sequential deposition of planar CH3NH3PbI3 (MAPbI3) film by using a novel volume-expansion-adjustable PbI2·xMAI (x: 0.1-0.3) precursor film to replace pure PbI2. The use of additive MAI during the first step of deposition leads to the reduced crystallinity of PbI2 and the pre-expansion of PbI2 into PbI2·xMAI with adjustable morphology, which result in about 10-fold faster formation of planar MAPbI3 film (without PbI2 residue) and thus minimize the negative impact of the solvent isopropanol on perovskites during the MAI intercalation/conversion step. The best efficiency obtained for a planar perovskite solar cell based on PbI2·0.15MAI is 17.22% (under one sun illumination), which is consistent with the stabilized maximum power output at an efficiency of 16.9%.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b00843
  • Yeliang Wang, Linfei Li, Wei Yao, Shiru Song, Jiatao Sun, Jinbo Pan, Xiao Ren, Chen Li, Eiji Okunishi, Yu-Qi Wang, [...], Eike F Schwier, Hideaki Iwasawa, Kenya Shimada, Masaki Taniguchi, Zhaohua Cheng, Shuyun Zhou, Shixuan Du, Stephen J Pennycook, Sokrates T Pantelides, Hong-Jun Gao
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    ABSTRACT: Single-layer transition-metal dichalcogenides (TMDs) receive significant attention due to their intriguing physical properties for both fundamental research and potential applications in electronics, optoelectronics, spintronics, catalysis, and so on. Here we demonstrate the epitaxial growth of high-quality single-crystal, monolayer platinum diselenide (PtSe2), a new member of the layered TMDs family, by a single step of direct selenization of a Pt(111) substrate. A combination of atomic-resolution experimental characterizations and first-principle theoretic calculations reveals the atomic structure of the monolayer PtSe2/Pt(111). Angle-resolved photoemission spectroscopy measurements confirm for the first time the semiconducting electronic structure of monolayer PtSe2 (in contrast to its semimetallic bulk counterpart). The photocatalytic activity of monolayer PtSe2 film is evaluated by a methylene-blue photodegradation experiment, demonstrating its practical application as a promising photocatalyst. Moreover, circular polarization calculations predict that monolayer PtSe2 has also potential applications in valleytronics.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b00964
  • Zhen Li, Goutham Ezhilarasu, Ioannis Chatzakis, Rohan Dhall, Chun-Chung Chen, Stephen B Cronin
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    ABSTRACT: Transition metal dichalcogenides (TMDCs), such as MoS2 and WSe2, are free of dangling bonds, and therefore make more 'ideal' Schottky junctions than bulk semiconductors, which produce Fermi energy pinning and recombination centers at the interface with bulk metals, inhibiting charge transfer. Here, we observe a more than 10X enhancement in the indirect band gap photoluminescence of transition metal dichalcogenides (TMDCs) deposited on various metals (e.g., Cu, Au, Ag), while the direct band gap emission remains unchanged. We believe the main mechanism of light emission arises from photoexcited hot electrons in the metal that are injected into the conduction band of MoS2 and WSe2, and subsequently recombine radiatively with minority holes in the TMDC. Since the conduction band at the K-point is 0.5eV higher than at the Σ-point, a lower Schottky barrier exists for the Σ-point band, making electron injection more favorable. Also, the Σ band consists of the sulfur pz orbital, which overlaps more significantly with the electron wavefunctions in the metal. This enhancement in the indirect emission only occurs for thick flakes of MoS2 and WSe2 (≥100nm), and is completely absent in monolayer and few-layer (~10nm) flakes. Here, the flake thickness must exceed the depletion width of the Schottky junction, in order for efficient radiative recombination to occur in the TMDC. The intensity of this indirect peak decreases at low temperatures, which is consistent with the hot electron injection model.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b00885
  • Samik Mukherjee, Uri Givan, Stephan Senz, Alaric Bergeron, Sébastien Francoeur, María de la Mata, Jordi Arbiol, Takeharu Sekiguchi, Kohei M Itoh, Dieter Isheim, David N Seidman, Oussama Moutanabbir
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    ABSTRACT: The introduction of stable isotopes in the fabrication of semiconductor nanowires provides an additional degree of freedom to manipulate their basic properties, design an entirely new class of devices, and highlight subtle but important nanoscale and quantum phenomena. With this perspective, we report on phonon engineering in metal catalyzed silicon nanowires with tailor-made isotopic compositions grown using isotopically enriched silane precursors 28SiH4, 29SiH4, and 30SiH4 with purity better than 99.9%. More specifically, isotopically mixed nanowires 28Six30Si1-x with a composition close to the highest mass disorder (x ~ 0.5) were investigated. The effect of mass disorder on the phonon behavior was elucidated and compared to that in isotopically pure 29Si nanowires having a similar reduced mass. We found that the disorder-induced enhancement in phonon scattering in isotopically mixed nanowires is unexpectedly much more significant than in bulk crystals of close isotopic compositions. This effect is explained by a non-uniform distribution of 28Si and 30Si isotopes in the grown isotopically mixed nanowires with local compositions ranging from x = 0.25 to 0.70. Moreover, we also observed that upon heating phonons in 28Six30Si1-x nanowires behave remarkably differently from those in 29Si nanowires suggesting a reduced thermal conductivity induced by mass disorder. Using Raman nanothermometry, we found that the thermal conductivity of isotopically mixed 28Six30Si1-x nanowires is ~30% lower than that of isotopically pure 29Si nanowires in agreement with theoretical predictions.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b00708
  • Andrew Barnabas Wong, Sarah Brittman, Yi Yu, Neil P Dasgupta, Peidong Yang
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    ABSTRACT: As an earth-abundant p-type semiconductor, copper sulfide (Cu2S) is an attractive material for application in photovoltaic devices. However, it suffers from a minority carrier diffusion length that is less than the length required for complete light absorption. Core-shell nanowires and nanorods have the potential to alleviate this difficulty because they decouple the length scales of light absorption and charge collection. To achieve this geometry using Cu2S, cation exchange was applied to an array of CdS nanorods to produce well-defined CdS-Cu2S core-shell nanorods. Previous work has demonstrated single-nanowire photovoltaic devices from this material system, but in this work, the cation exchange chemistry has been applied to nanorod arrays to produce ensemble-level devices with microscale sizes. The core-shell nanorod array devices show power conversion efficiencies of up to 3.8%. In addition, these devices are stable when measured in air after nearly one month of storage in a desiccator. These results are a first step in the development of large-area nanostructured Cu2S-based photovoltaics that can be processed from solution.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b01203
  • Michel Nasilowski, Piernicola Spinicelli, Gilles Patriarche, Benoit Dubertret
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    ABSTRACT: Auger recombination is a major limitation for the fluorescent emission of quantum dots. It is the main source of QDs fluorescence blinking at the single particle level. At high power excitation when several charge carriers are formed inside a QD, Auger becomes more efficient and severely decreases the quantum yield of multi-excitons. This limits the efficiency and the use of colloidal QDs in applications where intense light output is required. Here, we present a new generation of thick-shell CdSe/CdS QDs with dimensions > 40 nm and a composition gradient between the core and the shell that exhibit 100% QY for the emission of both the monoexciton and the biexciton in air and at room temperature for all the QDs we have observed. The fluorescence emission of these QDs is perfectly poissonian at the single particle level at different excitation levels and temperatures, from 30K to 300K. In these QDs, the emission of high order (>2) multiexcitons is quite efficient, and we observe white light emission at the single QD level when high excitation power is used. These gradient thick shell QDs confirm the suppression of Auger recombination in gradient core/shell structures and help further establish the colloidal QDs with a gradient shell as a very stable source of light even under high excitation.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b00838
  • Samuel D Stranks, Simon M Wood, Konrad Wojciechowski, Felix Deschler, Michael Saliba, Hitesh Khandelwal, Jay B Patel, Steve Elston, Laura M Herz, Michael B Johnston, Albertus P H J Schenning, Michael G Debije, Moritz Riede, Stephen M Morris, Henry J Snaith
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    ABSTRACT: Organic-inorganic perovskites are highly promising solar cell materials, with laboratory-based power conversion efficiencies already matching those of established thin film technologies. Their exceptional photovoltaic performance is in part attributed to the presence of efficient radiative recombination pathways, thereby opening up the possibility of efficient light-emitting devices. Here, we demonstrate optically-pumped amplified spontaneous emission (ASE) at 780 nm from a 50-nm-thick film of CH3NH3PbI3 perovskite that is sandwiched within a cavity comprised of a thin-film (~7 μm) cholesteric liquid crystal (CLC) reflector and a metal back-reflector. The threshold fluence for ASE in the perovskite film is reduced by at least two orders of magnitude in the presence of the CLC reflector, resulting in a factor of 2 reduction in threshold fluence compared to previous reports. We consider this to be due to improved coupling of the oblique and out-of-plane modes that are reflected into the bulk in addition to any contributions from cavity modes. Furthermore, we also demonstrate enhanced ASE on flexible reflectors and discuss how improvements in the quality factor and reflectivity of the CLC layers could lead to single-mode lasing using CLC reflectors. Our work opens up the possibility of fabricating widely wavelength-tuneable 'mirror-less' single-mode lasers on flexible substrates, which could find use in applications such as flexible displays and friend or foe identification.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b00678
  • James F Matthaei, Frank DiMaio, Jeffrey J Richards, Lilo D Pozzo, David Baker, François Baneyx
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    ABSTRACT: We have combined fusion of oligomers with cyclic symmetry and computational redesign of packing interfaces to produce proteins that self-assemble into 2-D arrays upon addition of calcium ions. Using TEM, AFM, small-angle X-ray scattering and fluorescence microscopy, we show that the designed lattices which are 5 nm high with p3 space group symmetry and 7.25 nm periodicity, self-assemble into structures that can reach hundreds of micrometers. The versatile strategy, experimental approach, and hexagonal arrays described herein should prove valuable for the engineering of functional nanostructured materials in 2-D.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b01499
  • Xu Xu, Mengyu Yan, Xiaocong Tian, Chuchu Yang, Mengzhu Shi, Qiulong Wei, Lin Xu, Liqiang Mai
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    ABSTRACT: In the last decade, Li ion batteries are widely considered to be the most promising rechargeable batteries for the rapid development of mobile devices and electric vehicles. There is also much interest in Na ion batteries, especially in the field of static grid storage due to their much lower production cost compared with Li ion batteries. However, the fundamental mechanism of Li and Na ion transport in nanoscale electrodes of batteries has been rarely experimentally explored. This insight can guide the development and optimization of high-performance electrode materials. In this work, single nanowire devices with multi-contacts are designed to get detailed information during the electrochemical reactions. This unique platform is employed to in situ investigate and compare the transport properties of Li and Na ions at a single nanowire level. To give different confinement for ions and electrons during the electrochemical processes, two different configurations of nanowire electrode are proposed, one is to fully immerse the nanowire in the electrolyte and second one is using photoresist to cover the nanowire with only one end been exposed. For both configurations, the conductivity of nanowire decreases after intercalation/deintercalation for both Li and Na ions, indicating that they share the similar electrochemical reaction mechanisms in layered electrodes. However, the conductivity degradation and structure destruction for Na ions is more severe than those of Li ions during the electrochemical processes, which mainly results from the much larger volume of Na ions and greater resistance force encountered by the limited layered spaces. Moreover, the battery performances of coin cells are compared to further confirm this conclusion. The present work provides a unique platform for in situ electrochemical and electrical probing, which will push the fundamental and practical research of nanowire electrode materials for energy storage applications.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b00705
  • Rong Sun, Daniel Jacobsson, I-Ju Chen, Malin Nilsson, Claes Thelander, Sebastian Lehmann, Kimberly A Dick
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    ABSTRACT: The widespread use of Au as a seed particle in the fabrication of semiconductor nanowires presents a fundamental limitation to the potential incorporation of such nanostructures into electronic devices. Although several other growth techniques have been demonstrated, the use of alternative seed particle metals remains an underexplored but potentially very promising way to influence the properties of the resulting nanowires while simultaneously avoiding gold. In this letter we demonstrate the use of Sn as a seed particle metal for GaAs nanowires grown by metal-organic vapor phase epitaxy. We show that vertically-aligned and stacking defect-free GaAs nanowires can be grown with very high yield. The resulting nanowires exhibit Esaki diode behavior, attributed to very high n-doping of the nanowire core with Sn, and simultaneous C-doping of the radially overgrowth. These results demonstrate that the use of alternative seed particle metals is a potentially important area to explore for developing nanowire materials with controlled material properties.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b00276
  • James Luke Webb, Johan Valentin Knutsson, Martin Hjort, Sepideh Gorji Ghalamestani, Kimberly A Dick, Rainer Timm, Anders Mikkelsen
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    ABSTRACT: We present a study of InAs/InSb heterostructured nanowires by x-ray photoemission spectroscopy (XPS), scanning tunneling microscopy (STM) and in-vacuum electrical measurements. Starting with pristine nanowires covered only by the native oxide formed through exposure to ambient air, we investigate the effect of atomic hydrogen cleaning on the surface chemistry and electrical performance. We find that clean and unreconstructed nanowire surfaces can be obtained simultaneously for both InSb and InAs by heating to 380C+/-20C under an hydrogen pressure of 2x10^-6mbar. Through electrical measurement of individual nanowires, we observe an increase in conductivity of 2 orders of magnitude by atomic hydrogen cleaning. Our study demonstrates the significant potential of atomic hydrogen cleaning regarding device fabrication when high quality contacts or complete control of the surface structure is required. As hydrogen cleaning has recently been shown to work for many different types of III-V nanowires our findings should be applicable far beyond the present materials system.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b00282
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    ABSTRACT: Rechargeable magnesium batteries have lately received great attention for large-scale energy storage systems due to their high volumetric capacities, low materials cost, and safe characteristic. However, the bivalency of Mg2+ ions has made it challenging to find cathode materials operating at high voltages with decent (de)intercalation kinetics. In an effort to overcome this challenge, we adopt an unconventional approach of engaging crystal water in the layered structure of Birnessite MnO2 because the crystal water can effectively screen electrostatic interactions between Mg2+ ions and the host anions. The crucial role of the crystal water was revealed by directly visualizing its presence and dynamic rearrangement using scanning transmission electron microscopy (STEM). Moreover, the importance of lowering desolvation energy penalty at the cathode-electrolyte interface was elucidated by working with water containing non-aqueous electrolytes. In aqueous electrolytes, the decreased interfacial energy penalty by hydration of Mg2+ allows Birnessite MnO2 to achieve a large reversible capacity (231.1 mAh g-1) at high operating voltage (2.8 V vs. Mg/Mg2+) with excellent cycle life (62.5% retention after 10,000 cycles), unveiling the importance of effective charge shielding in the host and facile Mg2+ ions transfer through the cathode's interface.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b01109
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    ABSTRACT: We present the first observation of Janus nanoparticles consisting of stable, co-existing ordered mesophases in discrete particles created by lipid self-assembly. Cryo-TEM images provided visual identification of the multi-compartment Janus nanoparticles and, combined with SAXS data, confirmed the presence of mixed cubic phases and mixed cubic/hexagonal phases within individual nanoparticles. We further investigated computer visualisation models to interpret the potential interface between the interconnected co-existing nanostructured domains within a single nanoparticle.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b01751
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    ABSTRACT: Phased-antenna metasurfaces can impart abrupt, spatially-dependent changes to the amplitude, phase, and polarization of light and thus mold wavefronts in a desired fashion. Here we present an experimental and computational near-field study of metasurfaces based on near-resonant V-shaped antennas, and connect their near- and far-field optical responses. We show that far-fields can be obtained from limited, experimentally-obtained knowledge of the near-fields, paving the way for experimental near-field characterization of metasurfaces and other optical nanostructures and prediction of their far-fields from the near-field measurements.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b00692
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    ABSTRACT: We investigate the phase-dependent excitation of localized surface plasmon polaritons in coupled nanorods by using nonlinear spectroscopy. Our design of a coupled three-nanorod structure allows independent excitation with cross-polarized light. Here, we show that the excitation of a particular plasmon mode can be coherently controlled by changing the relative phase of two orthogonally polarized light fields. Furthermore, we observe a phase relation for the excitation that is dominantly caused by damping effects.
    Nano Letters 05/2015; DOI:10.1021/acs.nanolett.5b01381