Plasmonic Nanocone Fabrication and Applications

Plasmonic nanocones represent a class of metallic nanostructures in which three-dimensional tapered geometries concentrate electromagnetic fields at sharp apices, harnessing localised surface plasmon resonances to achieve extraordinary light–matter interactions. Fabrication strategies span top-down approaches such as electron-beam lithography combined with angled film evaporation or focused ion beam patterning, and bottom-up routes including metal-assisted chemical etching and templated self-assembly. Control over cone angle, tip radius and spatial arrangement enables precise tuning of resonance wavelength, field enhancement factor and mode volume. Applications leverage the intense near-field hotspots for surface-enhanced spectroscopies (Raman, fluorescence, two-photon processes), nanoscale optical antennas for enhanced emitter radiation rates, and sensors with single-molecule sensitivity. Recent advances have delivered robust, large-area arrays for metamaterials and bespoke scanning probes for nanoscale imaging. These developments underscore the global significance of plasmonic nanocones across photonic circuitry, biomedical diagnostics, environmental monitoring and energy harvesting.

Research from Nature Portfolio

Recent studies have demonstrated a versatile top-down approach combining electron-beam lithography with tilted, rotating thermal evaporation to sculpt metallic nanocone arrays with precisely tunable apex angles and heights. By varying the deposition angle between 1° and 24°, a range of three-dimensional nanocone profiles—sharp-tipped, flat-bottomed spikes or hollow cylindrical structures—can be realised with critical dimensions well below the lithographic feature size. This process yields uniform arrays characterised by electron microscopy and predictive topographic modelling, and offers a generic route to integrate nanocone-based photonic elements and metamaterials into standard planar processes.

Plasmonic Nanocone Fabrication and Applications publication trend

The graph below shows the total number of articles in plasmonic nanocone fabrication and applications across all publications each year (not limited to Nature Index journals).

Technical terms

Localised surface plasmon resonance (LSPR): Collective oscillation of conduction electrons at a metallic nanostructure that produces strong confinement of the electromagnetic field.

Surface-enhanced Raman spectroscopy (SERS): Analytical technique exploiting plasmonic nanostructures to amplify weak Raman signals for trace-level molecular detection.

Focused ion beam (FIB) milling: Subtractive fabrication method using a focused beam of ions to sculpt nanoscale structures with high precision.

Metal-assisted chemical etching (MACE): Wet-chemical technique employing metal nanoparticles as catalysts to produce high-aspect-ratio silicon nanocones or nanowires.

Finite-difference time-domain (FDTD) simulations: Numerical analysis method for solving Maxwell’s equations to predict electromagnetic behaviour in complex nanostructures.

References

1. Size and shape control of a variety of metallic nanostructures using tilted, rotating evaporation and lithographic lift-off techniques. Scientific Reports (2019).
2. Nanofocusing of a metallized double periodic arranged nanocone array for surface-enhanced Raman spectroscopy.. Optics Express (2021).
3. Plasmonic Nanocone Scanning Antenna: Fabrication and Optical Properties. Advanced Photonics Research (2023).