Direct Observation of Plasmonic Modes in Au Nanowires Using High-Resolution Cathodoluminescence Spectroscopy

Vesseur, Ernst Jan R.; Waele, René de; Kuttge, M.; Polman, A.

doi:10.1021/nl071480w

Cited by 273 publications

(306 citation statements)

References 13 publications

Supporting

Mentioning

298

Contrasting

Order By: Relevance

“…Similar to Figure 2a, the maximum of the emission intensity exhibits oscillations as the diameter D is increased and are caused by the formation of FP resonances in the nanowires. 26,27 The periodicity of these oscillations increases with the diameter D because the wavelengths of wire plasmons of a fixed energy are proportional to D. 28 In the experiment we observed some variations of the emission intensities between different wires of similar diameters. These observations are consistent with the results in Figure 2 showing that the emission intensity depends sensitively on both the length and diameter of the wire.…”

mentioning

confidence: 78%

Directional Light Emission from Propagating Surface Plasmons of Silver Nanowires

et al. 2009

View full text Add to dashboard Cite

Thin metallic nanowires are highly promising candidates for plasmonic waveguides in photonic and electronic devices. We have observed that light from the end of a silver nanowire, following excitation of plasmons at the other end of the wire, is emitted in a cone of angles peaking at nominally 45-60°from the nanowire axis, with virtually no light emitted along the direction of the nanowire. This surprising characteristic can be explained in a simple picture invoking Fabry-Pérot resonances of the forward-and back-propagating plasmons on the nanowire. This strongly angular-dependent emission is a critical property that must be considered when designing coupled nanowire-based photonic devices and systems.Plasmonic waveguides have significant potential to be used as a key component in miniaturized optical devices at the nanometer scale, and in the integration of photonic circuits with electronics to overcome the limitations of bandwidth and data transmission rates of classical electrical interconnects.1-8 Such an integration of photonics and electronics and the miniaturization of optical devices at the nanometer size are of considerable current interest in nanophotonics. 8 When surface plasmon polaritons (SPPs), 9 the collective motion of free electrons, are excited in the plasmonic waveguides, they can be propagated at distances exceeding tens of micrometers, in nanometer-width geometries such as nanoparticle chains, 10-12 metal stripes, 13 grooves, 14 metal-insulator-metal structures, 7,15 and nanowires. [16][17][18][19][20] While intensive experimental and theoretical efforts have focused on improving the in-coupling efficiency of light 3,19 and on how to reduce the propagation loss, 4,21 relatively little is known about their light-emitting properties.22 This is critically important information for the design and development of SPP waveguides in integrated photonic or electronic devices and systems.In this paper, we measure the spatial distribution of the light emitted from one end of a nanowire following the excitation of SPPs at the other end. Surprisingly, we find that almost no light is emitted in the direction of the nanowire but instead peaked at nominally 45-60°from the direction of the wire. For thin nanowires we observe that the distribution of the emitted light is remarkably insensitive to the diameter and length of the nanowire and the detailed structure of the wire ends.Several different approaches have been developed for the imaging of plasmonic properties of metallic nanostructures. 23,24 In the present work, the SPPs are excited by focusing a laser beam through an objective to one end of the nanowire, which is shown in Figure 1a. The emission from the other end of the nanowire is collected by the same objective and the optical image is recorded by a TE cooled 1392 × 1040 CCD detector mounted on a microscope (Olympus BX51). The intensity of the emission is determined by finding the maximum value in the emission spot from the optical image. The objective itself has an inside iris diaphragm w...

show abstract

mentioning

confidence: 78%

Directional Light Emission from Propagating Surface Plasmons of Silver Nanowires

et al. 2009

View full text Add to dashboard Cite

show abstract

“…Arguably, it is the combination of optical monochromator resolution (easily below 1 meV) with multichannel detection (for hyperspectral imaging) that provides the strongest impetus for the application of CL also to metallic nanostructures. 87 E.g., SPP modes and their symmetries have been studied by CL in noble metal wires 86,88 (Fig. 5), and triangular nanoprisms.…”

Section: Electron-in/photon-out Methodsmentioning

confidence: 99%

Real-space imaging of nanoplasmonic resonances

Vogelgesang

Dmitriev

2010

Analyst

View full text Add to dashboard Cite

Resonant nanoplasmonic structures have long been recognized for their unique applications in subwavelength control of light for enhanced transmission, focussing, field confinement, decay rate management, etc. Increasingly, they are also integrated in electro-optical analytical sensors, shrinking the active volume while at the same time improving sensitivity and specificity. The microscopic imaging of resonances in such structures and also their dynamic variations has seen dramatic advances in recent years. In this Minireview we outline the current status of this rapidly evolving field, discussing both optical and electron microscopy approaches, the limiting issues in spatial resolution and data interpretation, the quantities that can be recorded, as well as the growing importance of time-resolving methods.

show abstract

“…Fast electrons can launch plasmons in laterally confined waveguides, for instance, in a metallic wire 14 or in any translationally invariant structure. As a result of this, a detectable electron energy-loss signal should be produced.…”

Section: Calculation Methodsmentioning

confidence: 99%

“…11 In a related context, localized plasmons have also been excited by electron beams, giving rise to characteristic cathodoluminescence emission features that allow one to measure their spatial variations with the characteristic nanometer resolution of electron microscopes. [12][13][14][15][16][17] Propagating gap plasmons are well understood from a theoretical point of view. 7 Notice that these plasmons are quite different from the resonances that one obtains associated to the excitation of wire pairs using light incident normal to the wires.…”

Section: Introductionmentioning

confidence: 99%

Controllable excitation of gap plasmons by electron beams in metallic nanowire pairs

et al. 2010

View full text Add to dashboard Cite

We show that electron beams can efficiently excite gap-plasmon modes in metallic waveguides defined by nanowire pairs. These modes are characterized by monopole-monopole charge symmetry. Significant excitation yields of higher-order dipole-dipole and quadrupole-quadrupole modes are also predicted. Our results are based on rigorous numerical solution of Maxwell's equations in which the electron is described as a classical external current. In our analysis, we find it convenient to simulate electron energy-loss spectra, which are resolved in the frequency and parallel momentum transferred from the electron to the wires for various perpendicular electron trajectories. The charge symmetry of these modes is inferred from the distribution of the induced near fields. The emission yield for the gap modes is as high as 10 −4 plasmons per incoming electron over the visible range of frequencies. Higher-order modes can be selectively excited by playing with the orientation of the electron trajectory whereas the gap plasmon is preferentially launched in nonsymmetric configurations and it is totally suppressed in symmetric arrangements. The effect of curvature along the direction of the wires is also explored by considering the excitation of plasmons defined in the gap between two circularly shaped wires. Our results provide full support for the excitation of gap plasmons with designated electron-beam sources in nanocircuits.

show abstract

Direct Observation of Plasmonic Modes in Au Nanowires Using High-Resolution Cathodoluminescence Spectroscopy

Cited by 273 publications

References 13 publications

Directional Light Emission from Propagating Surface Plasmons of Silver Nanowires

Directional Light Emission from Propagating Surface Plasmons of Silver Nanowires

Real-space imaging of nanoplasmonic resonances

Controllable excitation of gap plasmons by electron beams in metallic nanowire pairs

Contact Info

Product

Resources

About