Three-dimensional optical antennas: Nanocones in an apertureless scanning near-field microscope

Fleischer, Monika; Stanciu, C.; Stade, F.; Stadler, Johannes; Braun, Kai; Heeren, A.; Häffner, M.; Kern, D. P.; Meixner, Alfred J.

doi:10.1063/1.2987485

Cited by 55 publications

(79 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The fitted curve shows that the CAS signal has a cos 6 (q) scattering dependence, which demonstrates that the CAS signal originates from a third-order nonlinear process, in agreement with observations by Kim et al [17] We also verified the imaging capability of nanoscale gold structures by generating coherent anti-Stokes signals from patterned nanoparticle assemblies. Here, the sample was prepared by drying a droplet of the GNR solution on a piece of silicon wafer, which caused the formation of irregular patterns in the interior of the dried spot.…”

Section: Resultssupporting

confidence: 85%

“…CAS imaging visualized evenly distributed GNRs and the intensity of the CAS signal was proportional to the square of the particle number density. When GNRs were regularly oriented, the CAS signal was demonstrated to show a cos 6 (q) dependence on the angle between the polarization of the excitation beams and the longitudinal axis of the GNRs. This relationship confirmed that CAS emission by GNRs was a nonlinear, third-order process and that the CAS signal originated from the excitation of surface plasmon resonances in the nanorods.…”

Section: Discussionmentioning

confidence: 98%

“…Irregularly oriented GNRs exhibited a different scattering pattern to that observed for regularly oriented GNRs. The polarization-dependent scattering from oriented GNRs showed cos 6 (q) behavior. By imaging nanoscale-sized GNR patterns using CAS and evaluating the results with SEM, we show that CAS can be used for efficient, label-free imaging of nanoscale metallic particles.…”

Section: Introductionmentioning

confidence: 95%

“…[ [3][4][5][6] The effects of electromagnetic field enhancement at metallic surfaces can also be observed during nonlinear excitations and have previously been used for third-harmonic generation (THG), [7] two-photon-excited luminescence (TPEL), [8] and as contrast mechanisms for biomedical imaging. [9,10] This approach is complementary to fluorescence microscopy, but in some aspects it is also advantageous, because the signal obtained from metallic nanoparticles is photostable and does not exhibit blinking behavior, which is the case for organic fluorophores.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Coherent Anti‐Stokes Emission from Gold Nanorods and its Potential for Imaging Applications

et al. 2013

View full text Add to dashboard Cite

We used coherent anti-Stokes scattering (CAS) to characterize individual gold nanorods (GNRs) and GNR aggregates. By creating samples with different densities of GNRs on silicon wafer substrates, we were able to determine surface coverage by scanning electron microscopy (SEM) and then correlate the coverage to the CAS intensities of the samples. The observed CAS signal intensity was quadratically dependent on the number of particles. We also examined the CAS signal as a function of the excitation polarization and found that the strongest signals in regularly oriented GNRs were observed when the beam polarization was aligned with the longitudinal axis of the GNRs. Irregularly oriented GNRs exhibited a different scattering pattern to that observed for regularly oriented GNRs. The polarization-dependent scattering from oriented GNRs showed cos(6)(θ) behavior. By imaging nanoscale-sized GNR patterns using CAS and evaluating the results with SEM, we show that CAS can be used for efficient, label-free imaging of nanoscale metallic particles.

show abstract

Section: Resultssupporting

confidence: 85%

Section: Discussionmentioning

confidence: 98%

Section: Introductionmentioning

confidence: 95%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Coherent Anti‐Stokes Emission from Gold Nanorods and its Potential for Imaging Applications

et al. 2013

View full text Add to dashboard Cite

show abstract

“…These aggregates have very promising potentials in applications like biosensing, [58,59,60] subwavelength waveguiding, [61,62] metamaterial applications, [63,64,65] imaging and fluorescence applications, [66,67,68] This coupling depends on wire-substrate separation and the dielectric permittivity of the substrate. For strongly absorbing substrates, the substrate-induced damping can be very large.…”

Section: Chapter 6 Conclusionmentioning

confidence: 99%

Plasmon hybridization for real metals

2010

View full text Add to dashboard Cite

Plasmon Hybridization in Real Metals by Kui BaoBy treating free electrons in metallic nanostructures as incompressible and irrotational fluid, Plasmon hybridization (PH) method can be used as a very useful tool in interpolating the electric magnetic behaviors of complex metallic nanostructures.Using PH theory and Finite Element Method (FEM), we theoretically investigated the optical properties of some complex nanostructrus induding coupled nanoparticle aggregates and nanowires.We investigated the plasmonic properties of a symmetric silver sphere heptamer and showed that the extinction spectrum exhibited a narrow Fano resonance. Using the plasmon hybridization approach and group theory we showed that this Fano resonance is caused by the interference of two bonding dipolar subradiant and superradiant plasmon modes of El u symmetry. We investigate the effect of structural symmetry breaking and show that the energy and shape of the Fano resonance can be tuned over a broad wavelength range. We show that the wavelength of the Fano resonance depends very sensitively on the dielectric permittivity of the surrounding media.Besides heptamer, we also used plasmon hybridization method and finite element method to investigate the plasmonic properties of silver or gold nano spherical clusters. For symmetric clusters, we show how group theory can be used to identify the microscopic nature of the plasmon resonances. For larger dusters, we show that narrow Fano resonances are frequently present in their optical spectra. As an example of asymmetric clusters, we demonstrate that clusters of four identical spherical particles support strong Fano-like interference. This feature is highly sensitive to the polarization of the incident electric field due to orientation-dependent coupling between particles in the cluster.~anowire plasmons can be launched by illumination at one terminus of the nanowire and emission can be detected at the other end of the wire. \Vith PH theory we can predict how the polarization of the emitted light depends on the polarization of the incident light. Depending on termination shape, a nanowire can serve as either a polarization-maintaining waveguide, or as a polarization-rotating, nanoscale halfwave plate. \Ve also investigated how the properties of a nearby substrate modify the excitation and propagation of plasmons in subwavelength silver wires.

show abstract

Photoinduced Temperature Gradients in Sub‐Wavelength Plasmonic Structures: The Thermoplasmonics of Nanocones

Cunha

Guo

Koya

et al. 2020

Advanced Optical Materials

View full text Add to dashboard Cite

Plasmonic structures are renowned for their capability to efficiently convert light into heat at the nanoscale. However, despite the possibility to generate deep sub‐wavelength electromagnetic hot spots, the formation of extremely localized thermal hot spots is an open challenge of research, simply because of the diffusive spread of heat along the whole metallic nanostructure. Here this challenge is tackled by exploiting single gold nanocones. It is theoretically shown how these structures can indeed realize extremely high temperature gradients within the metal, leading to deep sub‐wavelength thermal hot spots, owing to their capability of concentrating light at the apex under resonant conditions even under continuous wave illumination. A 3D finite element method model is employed to study the electromagnetic field in the structure and subsequent thermoplasmonic behavior, in terms of the 3D temperature distribution. How the latter is affected by nanocone size, shape, and composition of the surrounding environment is shown. Finally, the use of photoinduced temperature gradients in nanocones is anticipated for applications in optofluidics and thermoelectrics or for thermally induced nanofabrication.

show abstract

Three-dimensional optical antennas: Nanocones in an apertureless scanning near-field microscope

Cited by 55 publications

References 21 publications

Coherent Anti‐Stokes Emission from Gold Nanorods and its Potential for Imaging Applications

Coherent Anti‐Stokes Emission from Gold Nanorods and its Potential for Imaging Applications

Plasmon hybridization for real metals

Photoinduced Temperature Gradients in Sub‐Wavelength Plasmonic Structures: The Thermoplasmonics of Nanocones

Contact Info

Product

Resources

About