Electromagnetic Wave Propagation Close to Microstructures Studied by Time and Phase-Resolved THz Near-Field Imaging

Article

Abstract

We demonstrate microscopic mapping of electromagnetic waves close to metal microstructures with sub-ps temporal and sub-wavelength spatial resolution by pulsed THz near-field imaging. The inherent phase-sensitivity of this technique allows mapping wavefronts of propagating modes and the measured amplitude distributions provide information on field concentration and localization close to the structures. Using this approach we investigate wave propagation through a sub-wavelength aperture, as well as the formation of traveling and standing surface waves along a metal microwire.

Keywords

Near-field imaging Terahertz imaging Microstructures Plasmonics 

References

  1. 1.
    H. Raether, Surface Plasmons (Springer-Verlag, 1988).Google Scholar
  2. 2.
    D. M. Mittleman, M. Gupta, R. Neelamani, R. G. Baraniuk, J. V. Rudd, and M. Koch, “Recent advances in terahertz imaging,” Appl. Phys. B 68(6), 1085–1094 (1999).CrossRefGoogle Scholar
  3. 3.
    W. L. Chan, J. Deibel, and D. M. Mittleman, “Imaging with terahertz radiation,” Rep. Prog. Phys. 70(8), 1325–1379 (2007).CrossRefGoogle Scholar
  4. 4.
    M. Walther, B. M. Fischer, A. Ortner, A. Bitzer, A. Thoman, and H. Helm, “Chemical sensing and imaging with pulsed terahertz radiation,” Anal. Bioanal. Chem. 397(3), 1009–1017 (2010).CrossRefGoogle Scholar
  5. 5.
    Q. Chen, Z. P. Jiang, G. X. Xu, and X. C. Zhang, “Near-field terahertz imaging with a dynamic aperture,” Opt. Lett. 25(15), 1122–1124 (2000).CrossRefGoogle Scholar
  6. 6.
    S. Hunsche, M. Koch, I. Brener, and M. C. Nuss, “THz near-field imaging,” Opt. Comm. 150(1-6), 22–26 (1998).CrossRefGoogle Scholar
  7. 7.
    H. T. Chen, R. Kersting, and G. C. Cho, “Terahertz imaging with nanometer resolution,” Appl. Phys. Lett. 83(15), 3009–3011 (2003).CrossRefGoogle Scholar
  8. 8.
    H. T. Chen, S. Kraatz, G. C. Cho, and R. Kersting, “Identification of a resonant imaging process in apertureless near-field microscopy,” Phys. Rev. Lett. 93(26), 267401 (2004).CrossRefGoogle Scholar
  9. 9.
    O. Mitrofanov, I. Brener, R. Harel, J. D. Wynn, L. N. Pfeiffer, K. W. West, and J. Federici, “Terahertz near-field microscopy based on a collection mode detector,” Appl. Phys. Lett. 77(22), 3496–3498 (2000).CrossRefGoogle Scholar
  10. 10.
    O. Mitrofanov, I. Brener, M. C. Wanke, R. R. Ruel, J. D. Wynn, A. J. Bruce, and J. Federici, “Near-field microscope probe for far infrared time domain measurements,” Appl. Phys. Lett. 77(4), 591–593 (2000).CrossRefGoogle Scholar
  11. 11.
    M. A. Seo, A. J. L. Adam, J. H. Kang, J. W. Lee, S. C. Jeoung, Q. H. Park, P. C. M. Planken, and D. S. Kim, “Fourier-transform terahertz near-field imaging of one-dimensional slit arrays: mapping of electric-field-, magnetic-field-, and Poynting vectors,” Opt. Express 15(19), 11781–11789 (2007).CrossRefGoogle Scholar
  12. 12.
    A. Bitzer, A. Ortner, and M. Walther, “Terahertz near-field microscopy with subwavelength spatial resolution based on photoconductive antennas,” Appl. Opt. 49(19), E1–E6 (2010).CrossRefGoogle Scholar
  13. 13.
    O. Mitrofanov, M. Lee, J. W. P. Hsu, L. N. Pfeiffer, K. W. West, J. D. Wynn, and J. F. Federici, “Terahertz pulse propagation through small apertures,” Appl. Phys. Lett. 79(7), 907–909 (2001).CrossRefGoogle Scholar
  14. 14.
    A. J. L. Adam, J. M. Brok, M. A. Seo, K. J. Ahn, D. S. Kim, J. H. Kang, Q. H. Park, M. Nagel, and P. C. M. Planken, “Advanced terahertz electric near-field measurements at sub-wavelength diameter metallic apertures,” Opt. Express 16(10), 7407–7417 (2008).CrossRefGoogle Scholar
  15. 15.
    A. Bitzer and M. Walther, “Terahertz near-field imaging of metallic subwavelength holes and hole arrays,” Appl. Phys. Lett. 92(23), 231101 (2008).CrossRefGoogle Scholar
  16. 16.
    L. Guestin, A. J. L. Adam, J. R. Knab, M. Nagel, and P. C. M. Planken, “Influence of the dielectric substrate on the terahertz electric near-field of a hole in a metal,” Opt. Express 17(20), 17412–17425 (2009).CrossRefGoogle Scholar
  17. 17.
    J. R. Knab, A. J. L. Adam, M. Nagel, E. Shaner, M. A. Seo, D. S. Kim, and P. C. M. Planken, “Terahertz Near-Field Vectorial Imaging of Subwavelength Apertures and Aperture Arrays,” Opt. Express 17(17), 15072–15086 (2009).CrossRefGoogle Scholar
  18. 18.
    G. Acuna, S. F. Heucke, F. Kuchler, H. T. Chen, A. J. Taylor, and R. Kersting, “Surface plasmons in terahertz metamaterials,” Opt. Express 16(23), 18745–18751 (2008).CrossRefGoogle Scholar
  19. 19.
    A. Bitzer, H. Merbold, A. Thoman, T. Feurer, H. Helm, and M. Walther, “Terahertz near-field imaging of electric and magnetic resonances of a planar metamaterial,” Opt. Express 17(5), 3826–3834 (2009).CrossRefGoogle Scholar
  20. 20.
    A. Bitzer, J. Wallauer, H. Helm, H. Merbold, T. Feurer, and M. Walther, “Lattice modes mediate radiative coupling in metamaterial arrays,” Opt. Express 17(24), 22108–22113 (2009).CrossRefGoogle Scholar
  21. 21.
    V. A. Fedotov, N. Papasimakis, E. Plum, A. Bitzer, M. Walther, P. Kuo, D. P. Tsai, and N. I. Zheludev, “Spectral Collapse in Ensembles of Metamolecules,” Phys. Rev. Lett. 104(22), 223901 (2010).CrossRefGoogle Scholar
  22. 22.
    A. Bitzer, A. Ortner, H. Merbold, T. Feurer, and M. Walther, “Terahertz near-field microscopy of complementary planar metamaterials: Babinet’s Principle,” Opt. Express 19(3), 2537–2545 (2011).CrossRefGoogle Scholar
  23. 23.
    M. Walther, G. S. Chambers, Z. G. Liu, M. R. Freeman, and F. A. Hegmann, “Emission and detection of terahertz pulses from a metal-tip antenna,” J. Opt. Soc. Am. B 22(11), 2357–2365 (2005).CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.Freiburg Materials Research Center (FMF)University of FreiburgFreiburgGermany
  2. 2.Institute of Applied PhysicsUniversity of BernBernSwitzerland

Personalised recommendations