Journal: Nano Letters

Abbreviation

Nano Lett

Publisher

American Chemical Society

Journal Volumes

ISSN

1530-6984
1530-6992

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Publications 1 - 10 of 389
  • Oscillating Magnetoresistance in Graphene p-n Junctions at Intermediate Magnetic Fields
    Item type: Journal Article
    Overweg, Hiske; Eggimann, Hannah; Liu, Ming-Hao; et al. (2017)
    Nano Letters
  • The Interplay of Shape and Crystalline Anisotropies in Plasmonic Semiconductor Nanocrystals
    Item type: Journal Article
    Kim, Jongwook; Agrawal, Ankit; Krieg, Franziska; et al. (2016)
    Nano Letters
    Doped semiconductor nanocrystals are an emerging class of materials hosting localized surface plasmon resonance (LSPR) over a wide optical range. Studies so far have focused on tuning LSPR frequency by controlling the dopant and carrier concentrations in diverse semiconductor materials. However, the influence of anisotropic nanocrystal shape and of intrinsic crystal structure on LSPR remain poorly explored. Here, we illustrate how these two factors collaborate to determine LSPR characteristics in hexagonal cesium-doped tungsten oxide nanocrystals. The effect of shape anisotropy is systematically analyzed via synthetic control of nanocrystal aspect ratio (AR), from disks to nanorods. We demonstrate the dominant influence of crystalline anisotropy, which uniquely causes strong LSPR band-splitting into two distinct peaks with comparable intensities. Modeling typically used to rationalize particle shape effects is refined by taking into account the anisotropic dielectric function due to crystalline anisotropy, thus fully accounting for the AR-dependent evolution of multiband LSPR spectra. This new insight into LSPR of semiconductor nanocrystals provides a novel strategy for an exquisite tuning of LSPR line shape.
  • Detection of a Chirality-Induced Spin Selective Quantum Capacitance in α-Helical Peptides
    Item type: Journal Article
    Theiler, Pius Markus; Ritz, Christian; Hofmann, Raphael; et al. (2023)
    Nano Letters
    Advanced Kelvin probe force microscopy simultaneously detects the quantum capacitance and surface potential of an α-helical peptide monolayer. These indicators shift when either the magnetic polarization or the enantiomer is toggled. A model based on a triangular quantum well in thermal and chemical equilibrium and electron–electron interactions allows for calculating the electrical potential profile from the measured data. The combination of the model and the measurements shows that no global charge transport is required to produce effects attributed to the chirality-induced spin selectivity effect. These experimental findings support the theoretical model of Fransson et al. Nano Letters 2021, 21 (7), 3026–3032. Measurements of the quantum capacitance represent a new way to test and refine theoretical models used to explain strong spin polarization due to chirality-induced spin selectivity.
  • Electrochemical Crystallization of Plasmonic Nanostructures
    Item type: Journal Article
    Dahlin, Andreas B.; Sannomiya, Takumi; Zahn, Raphael; et al. (2011)
    Nano Letters
  • Phonon-Mediated and Weakly Size-Dependent Electron and Hole Cooling in CsPbBr3 Nanocrystals Revealed by Atomistic Simulations and Ultrafast Spectroscopy
    Item type: Journal Article
    Boehme, Simon C.; ten Brinck, Stephanie; Maes, Jorick; et al. (2020)
    Nano Letters
  • Transport Through a Network of Topological Channels in Twisted Bilayer Graphene
    Item type: Journal Article
    Rickhaus, Peter; Wallbank, John; Slizovskiy, Sergey; et al. (2018)
    Nano Letters
  • Nanoscale Imaging of Current Density with a Single-Spin Magnetometer
    Item type: Journal Article
    Chang, K.; Eichler, Alexander; Rhensius, Jan; et al. (2017)
    Nano Letters
  • Resonant Light Emission from Graphene/Hexagonal Boron Nitride/Graphene Tunnel Junctions
    Item type: Journal Article
    Kuzmina, Anna; Parzefall, Markus; Back, Patrick; et al. (2021)
    Nano Letters
    Single-layer graphene has many remarkable properties but does not lend itself as a material for light-emitting devices as a result of its lack of a band gap. This limitation can be overcome by a controlled stacking of graphene layers. Exploiting the unique Dirac cone band structure of graphene, we demonstrate twist-controlled resonant light emission from graphene/hexagonal boron nitride (h-BN)/graphene tunnel junctions. We observe light emission irrespective of the crystallographic alignment between the graphene electrodes. Nearly aligned devices exhibit pronounced resonant features in both optical and electrical characteristics that vanish rapidly for twist angles θ ≳3°. These experimental findings can be well-explained by a theoretical model in which the spectral photon emission peak is attributed to photon-assisted momentum conserving electron tunneling. The resonant peak in our aligned devices can be spectrally tuned within the near-infrared range by over 0.2 eV, making graphene/h-BN/graphene tunnel junctions potential candidates for on-chip optoelectronics.
  • Spatial Resolution in Nanoscale TERS Imaging: Current Status, Challenges, and Guidelines
    Item type: Review Article
    Zenobi, Renato; Kumar, Naresh; Verma, Prabhat (2025)
    Nano Letters
    Tip-enhanced Raman spectroscopy (TERS) was invented almost 25 years ago and was quickly recognized as one of the few nano-optical techniques that confine light at the nanoscale to explore light-matter interactions at the nanoscale. Even several years after its invention, the spatial resolution in TERS studies is not only somewhat controversial, especially for AFM-based TERS measurements of samples at room temperature, but also not reported in the literature in a consistent, generally accepted fashion. This Mini-Review discusses the current situation and how spatial resolution in TERS is reported in different ways that yield different values because no standard method is defined. More importantly, the spatial resolution in TERS is influenced by various experimental conditions and other factors in a comprehensive fashion, which have often been ignored. We consider all possible factors that affect spatial resolution in TERS and provide guidelines on how to determine and report spatial resolution.
  • Fabrication and Characterization of Three-Dimensional InGaAs/GaAs Nanosprings
    Item type: Journal Article
    Bell, Dominik J.; Dong, Lixin; Nelson, Bradley J.; et al. (2006)
    Nano Letters
Publications 1 - 10 of 389