, Volume 42, Issue 8, pp 924–930 | Cite as

Edge effects in propagation of terahertz radiation in subwavelength periodic structures

Semiconductor Structures, Interfaces, and Surfaces


Improving detection sensitivity of biological molecules with low absorption characteristics in the terahertz gap still remains an important issue in terahertz vibrational resonance spectroscopy. One possible way to increase coupling of incident terahertz radiation to molecules is to exploit local enhancement of electromagnetic field in periodic slot arrays. In this work, we show that periodic arrays of rectangular slots with subwavelength widths provide for local electromagnetic field enhancements due to edge effects in our low frequency range of interest, 10–25 cm−1. Periodic structures of Au doped Si and InSb were studied. The half power enhancement width is ∼500 nm or less around the slot, edges in all cases, thereby possibly bringing terahertz sensing to the nanoscale. InSb is confirmed to offer the highest results with local power enhancements on the order of 1100 at frequency 14 cm−1. InSb and Si have large skin depths in our frequency range of interest and so the analysis of their structures was done through the Fourier expansion method of field diffracted from gratings. Surface impedance boundary conditions were employed to model the Au structure. The applications possibly include development of novel biosensors, and monitoring biophysical processes such as DNA denaturation.

PACS numbers

41.20.Jb 78.68.+m 78.70.Gq 


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  1. 1.
    T. Globus, D. Woolard, M. Bykhovskaia, et al., Int. J. High Speed Electron. Syst. 13, 903 (2003).CrossRefGoogle Scholar
  2. 2.
    T. Globus, D. Woolard, T. W. Crowe, et al., J. Phys. D: Appl. Phys. 39, 3405 (2006).CrossRefADSGoogle Scholar
  3. 3.
    A. Bykhovski, T. Globus, T. Khromova, et al., Proc. SPIE 6212, 62120H (2006).Google Scholar
  4. 4.
    M. E. McDonald, A. Alexanian, R. A. York, et al., IEEE Trans. Microwave Theory Tech. 48, 712 (2000).CrossRefGoogle Scholar
  5. 5.
    Electromagnetic Theory of Gratings, Ed. by R. Petit (Springer-Verlag, Berlin Heidelberg, 1980).Google Scholar
  6. 6.
    P. Sheng, R. S. Stepleman, and P. N. Sanda, Phys. Rev. B 26, 2907 (1982).CrossRefADSGoogle Scholar
  7. 7.
    H. E. Went, A. P. Hibbins, J. R. Sambles, et al., Appl. Phys. Lett. 77, 2789 (2000).CrossRefADSGoogle Scholar
  8. 8.
    Q. Cao and P. Lalanne, Phys. Rev. Lett. 88, 057403 (2002).Google Scholar
  9. 9.
    T. W. Ebbesen, H. J. Lezec, H. F. Ghaemi, Nature 391, 667 (1998).CrossRefADSGoogle Scholar
  10. 10.
    H. F. Ghaemi, T. Thio, D. E. Grupp, et al., Phys. Rev. B 58, 6779 (1998).CrossRefADSGoogle Scholar
  11. 11.
    T. Thio, H. F. Ghaemi, H. J. Lezec, et al., J. Opt. Soc. Am. B 16, 1743 (1999).CrossRefADSGoogle Scholar
  12. 12.
    E. Popov, M. Neviere, S. Enoch, and R. Reinisch, Phys. Rev. B 62, 16100 (2000).Google Scholar
  13. 13.
    L. Martin-Moreno, F. J. Garcia-Vidal, H. J. Lezec, et al., Phys. Rev. Lett. 86, 1114 (2001).CrossRefADSGoogle Scholar
  14. 14.
    S. A. Darmanyan and A. V. Zayats, Phys. Rev. B 67, 035424 (2003).Google Scholar
  15. 15.
    S. H. Chang and S. K. Gray, Opt. Express 13, 3150 (2005).CrossRefADSGoogle Scholar
  16. 16.
    H. Cao and A. Nahata, Opt. Express 12, 1004 (2004).CrossRefADSGoogle Scholar
  17. 17.
    D. Qu, D. Grischkowsky, and W. Zhang, Opt. Lett. 29, 896 (2004).CrossRefADSGoogle Scholar
  18. 18.
    J. Gomez Rivas, C. Schotsch, P. Haring Bolivar, and H. Kurz, Phys. Rev. B 68, 201306(R) (2003).Google Scholar
  19. 19.
    J. Gomez Rivas, C. Janke, P. Haring Bolivar, and H. Kurz, Opt. Express 13, 847 (2005).CrossRefADSGoogle Scholar
  20. 20.
    H. Raether, Surface Plasmons on Smooth and Rough Surfaces and on Gratings (Springer-Verlag, Berlin, 1988), Springer Tracts in Modern Physics, Vol. 111, Chs. 2, 4, 5.Google Scholar
  21. 21.
    E. Popov, S. Enoch, G. Tayeb, et al., Appl. Opt. 43, 999 (2004).CrossRefADSGoogle Scholar
  22. 22.
    J. W. Lee, M. A. Seo, D. J. Park, et al., Opt. Express 14, 12638 (2006).Google Scholar
  23. 23.
    J. A. Porto, F. J. Garcia-Vidal, and J. B. Pendry, Phys. Rev. Lett. 83, 2845 (1999).CrossRefADSGoogle Scholar
  24. 24.
    F. J. Garcia-Vidal and L. Martin-Moreno, Phys. Rev. B 66, 155412 (2002).Google Scholar
  25. 25.
    G. B. Arfken and H. J. Weber, Mathematical Methods for Physicists (Academic, New York, 1995), Ch. 14, p. 836.Google Scholar
  26. 26.
    A. Wirgin and T. Lopez-Rios, Opt. Commun. 48, 416 (1984).CrossRefADSGoogle Scholar
  27. 27.
    E. Litwin-Staszewska, W. Szymanska, and P. Piotrzkowski, Phys. Status Solidi B 106, 551 (1981).CrossRefGoogle Scholar
  28. 28.
    S. S. Li and W. R. Thurber, Solid State Electron. 20, 609 (1977).CrossRefADSGoogle Scholar
  29. 29.
    A. Heltzel, S. Theppakuttai, S. C. Chen, and J. R. Howell, Nanotechnology 19, 025305 (2008).Google Scholar
  30. 30.
    J. D. Jackson, Classical Electrodynamics (Wiley, New York, 1975), Ch. 2, p. 77.MATHGoogle Scholar
  31. 31.
    R. Parthasarathy, T. Globus, T. Khromova, et al., Appl. Phys. Lett. 87, 113901 (2005).Google Scholar
  32. 32.
    N. S. Swami, C. F. Chou, and R. Terberueggen, Langmuir 21, 1937 (2005).CrossRefGoogle Scholar
  33. 33.
    R. Parthasarathy, A. Bykhovski, B. Gelmont, et al., Phys. Rev. Lett. 98, 153906 (2007).Google Scholar

Copyright information

© Pleiades Publishing, Ltd. 2008

Authors and Affiliations

  1. 1.Department of Electrical & Computer EngineeringUniversity of VirginiaCharlottesvilleUSA

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