Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Nanomechanical control of an optical antenna


Resonant optical nanoantennas hold great promise for applications in physics and chemistry1,2,3,4,5,6. Their operation relies on their ability to concentrate light on spatial scales much smaller than the wavelength. In this work, we mechanically tune the length and gap between two triangles comprising a single gold bow-tie antenna by precise nanomanipulation with the tip of an atomic force microscope. At the same time, the optical response of the nanostructure is determined by means of dark-field scattering spectroscopy. We find no unique single ‘antenna resonance’. Instead, the plasmon mode splits into two dipole resonances for gap sizes on the order of a few tens of nanometres, governed by the full three-dimensional shape of the antenna arms. This result opens the door to new nano-optomechanical devices, where mechanical changes on the nanometre scale control the optical properties of artificial structures.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Rent or buy this article

Get just this article for as long as you need it


Prices may be subject to local taxes which are calculated during checkout

Figure 1: Nano-optomechanical set-up.
Figure 2: Topography and optical spectroscopy of the tunable nanoantenna.
Figure 3: Calculated backscattering spectra depending on the three-dimensional antenna shape.


  1. Sundaramurthy, A. et al. Toward nanometer-scale optical photolithography: Utilizing the near-field of bowtie optical nanoantennas. Nano Lett. 6, 355–360 (2006).

    Article  ADS  Google Scholar 

  2. Aizpurua, J. et al. Optical properties of coupled metallic nanorods for field-enhanced spectroscopy. Phys. Rev. B 71, 235420 (2005).

    Article  ADS  Google Scholar 

  3. Farahani, J. N., Pohl, D. W., Eisler, H. J. & Hecht, B. Single quantum dot coupled to a scanning optical antenna: A tunable superemitter. Phys. Rev. Lett. 95, 17402 (2005).

    Article  ADS  Google Scholar 

  4. Cubukcu, E., Kort, E. A., Crozier, K. B. & Capasso, F. Plasmonic laser antenna. Appl. Phys. Lett. 89, 93120 (2006).

    Article  Google Scholar 

  5. Novotny, L. Effective wavelength scaling for optical antennas. Phys. Rev. Lett. 98, 266802 (2007).

    Article  ADS  Google Scholar 

  6. Challenger, W. A. et al. Light delivery techniques for heat-assisted magnetic recording. Jpn J. Appl. Phys. 42, 981–988 (2003).

    Article  ADS  Google Scholar 

  7. Xu, H. & Käll, M. Surface-plasmon-enhanced optical forces in silver nanoaggregates. Phys. Rev. Lett. 89, 246802 (2002).

    Article  ADS  Google Scholar 

  8. Haes, A. J. & van Duyne, R. P. A nanoscale optical biosensor: Sensitivity and selectivity of an approach based on the localized surface plasmon resonance spectroscopy of triangular silver nanoparticles. J. Am. Chem. Soc. 124, 10596–10604 (2002).

    Article  Google Scholar 

  9. Schuck, P. J., Fromm, D. P., Sundaramurthy, A., Kino, G. S. & Moerner, W. E. Improving the mismatch between light and nanoscale objects with gold bowtie nanoantennas. Phys. Rev. Lett. 94, 17402 (2005).

    Article  ADS  Google Scholar 

  10. Mühlschlegel, P., Eisler, H.-J., Martin, O. J. F., Hecht, B. & Pohl, D. W. Resonant optical antennas. Science 308, 1607–1609 (2005).

    Article  ADS  Google Scholar 

  11. Fischer, U. C. & Zingsheim, H. P. Submicroscopic pattern replication with visible light. J. Vac. Sci. Technol. 19, 881–885 (1981).

    Article  ADS  Google Scholar 

  12. Deckman, H. W. & Dunsmuir, J. H. Natural lithography. Appl. Phys. Lett. 41, 377–379 (1982).

    Article  ADS  Google Scholar 

  13. Burmeister, F. et al. From mesoscopic to nanoscopic surface structures: Lithography with colloid monolayers. Adv. Mater. 10, 495–497 (1998).

    Article  Google Scholar 

  14. Draine, B. T. & Flatau, P. J. User Guide for the Discrete Dipole Approximation Code DDSCAT 6.1. <> (2004).

  15. Glang, R. Materials and processes for passive thin-film components. J. Vac. Sci Technol. 3, 37–48 (1966).

    Article  ADS  Google Scholar 

  16. Haq, K. E., Behrndt, K. H. & Kobin, I. Adhesion mechanism of gold-underlayer film combinations to oxide substrates. J. Vac. Sci Technol. 6, 148–152 (1969).

    Article  ADS  Google Scholar 

  17. Sundaramurthy, A. et al. Field enhancement and gap-dependent resonance in a system of two opposing tip-to-tip Au nanotriangles. Phys. Rev. B 72, 165409 (2005).

    Article  ADS  Google Scholar 

  18. Kelly, K. L., Coronado, E., Zhao, L. L. & Schatz, G. C. The optical properties of metal nanoparticles: The influence of size, shape, and dielectric environment. J. Phys. Chem. B 107, 668–677 (2003).

    Article  Google Scholar 

  19. Landau, L. D. & Lifshitz, E. M. Electrodynamics of Continuous Media (New York, Pergamon, 1960).

    MATH  Google Scholar 

  20. Göger, G. et al. Ultrafast spectroscopy of large-momentum excitons in GaAs. Phys. Rev. Lett. 84, 5812–5815 (2000).

    Article  ADS  Google Scholar 

  21. Betz, M. et al. Nonlinear optical response of highly energetic excitons in GaAs: Microscopic electrodynamics at semiconductor interfaces. Phys. Rev. B 65, 85314 (2002).

    Article  ADS  Google Scholar 

Download references


We gratefully acknowledge financial support from the Deutsche Forschungsgemeinschaft (DFG) through SFB 513, the Kompetenznetz Funktionelle Nanostrukturen Baden-Württemberg, and a grant from the Ministry of Science, Research and Arts Baden-Württemberg. We acknowledge the generous help of M. Fuchs, S. Gerlach, K. Diederichs, R. Stadelhofer and W. Benger by providing extensive computer power for the DDA calculations. We acknowledge the help of H. Ballot and A. Habenicht with the colloidal masks.

Author information

Authors and Affiliations



Jörg Merlein and Matthias Kahl contributed equally to this work.

Corresponding authors

Correspondence to Jörg Merlein, Matthias Kahl or Rudolf Bratschitsch.

Supplementary information

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Merlein, J., Kahl, M., Zuschlag, A. et al. Nanomechanical control of an optical antenna. Nature Photon 2, 230–233 (2008).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

This article is cited by


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing