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Virtual Journal for Biomedical Optics

Virtual Journal for Biomedical Optics

| EXPLORING THE INTERFACE OF LIGHT AND BIOMEDICINE

  • Editors: Andrew Dunn and Anthony Durkin
  • Vol. 8, Iss. 5 — Jun. 6, 2013

Plasmonic near-field probes: a comparison of the campanile geometry with other sharp tips

Wei Bao, Matteo Staffaroni, Jeffrey Bokor, Miquel B. Salmeron, Eli Yablonovitch, Stefano Cabrini, Alexander Weber-Bargioni, and P. James Schuck  »View Author Affiliations


Optics Express, Vol. 21, Issue 7, pp. 8166-8176 (2013)
http://dx.doi.org/10.1364/OE.21.008166


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Abstract

Efficient conversion of photonic to plasmonic energy is important for nano-optical applications, particularly imaging and spectroscopy. Recently a new generation of photonic/plasmonic transducers, the ‘campanile’ probes, has been developed that overcomes many shortcomings of previous near-field probes by efficiently merging broadband field enhancement with bidirectional coupling of far- to near-field electromagnetic modes. In this work we compare the properties of the campanile structure with those of current NSOM tips using finite element simulations. Field confinement, enhancement, and polarization near the apex of the probe are evaluated relative to local fields created by conical tapered tips in vacuum and in tip-substrate gap mode. We show that the campanile design has similar field enhancement and bandwidth capabilities as those of ultra-sharp metallized tips, but without the substrate and sample restrictions inherent in the tip-surface gap mode operation often required by those tips. In addition, we show for the first time that this campanile probe structure also significantly enhances the radiative rate of any dipole emitter located near the probe apex, quantifying the enhanced decay rate and demonstrating that over 90% of the light radiated by the emitter is “captured” by this probe. This is equivalent to collecting the light from a solid angle of ~3.6 pi. These advantages are crucial for performing techniques such as Raman and IR spectroscopy, white-light nano-ellipsometry and ultrafast pump-probe studies at the nanoscale.

© 2013 OSA

OCIS Codes
(300.0300) Spectroscopy : Spectroscopy
(180.4243) Microscopy : Near-field microscopy
(250.5403) Optoelectronics : Plasmonics

ToC Category:
Microscopy

History
Original Manuscript: February 8, 2013
Revised Manuscript: March 18, 2013
Manuscript Accepted: March 19, 2013
Published: March 28, 2013

Virtual Issues
Vol. 8, Iss. 5 Virtual Journal for Biomedical Optics

Citation
Wei Bao, Matteo Staffaroni, Jeffrey Bokor, Miquel B. Salmeron, Eli Yablonovitch, Stefano Cabrini, Alexander Weber-Bargioni, and P. James Schuck, "Plasmonic near-field probes: a comparison of the campanile geometry with other sharp tips," Opt. Express 21, 8166-8176 (2013)
http://www.opticsinfobase.org/vjbo/abstract.cfm?URI=oe-21-7-8166


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