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Resonance Characteristics of THz Metamaterials Based on a Drude Metal with Finite Permittivity

  • Jun, Seung Won (Department of Physics and Department of Energy Systems Research, Ajou University) ;
  • Ahn, Yeong Hwan (Department of Physics and Department of Energy Systems Research, Ajou University)
  • Received : 2018.06.21
  • Accepted : 2018.07.10
  • Published : 2018.08.25

Abstract

In most previous investigations of plasmonic and metamaterial applications, the metallic film has been regarded as a perfect electrical conductor. Here we demonstrate the resonance characteristics of THz metamaterials fabricated from metal film that has a finite dielectric constant, using finite-difference time-domain simulations. We found strong redshift and spectral broadening of the resonance as we decrease the metal's plasma frequency in the Drude free-electron model. The frequency shift can be attributed to the effective thinning of the metal film, originating from the increase in penetration depth as the plasma frequency decreases. On the contrary, only peak broadening occurs with an increase in the scattering rate. The metal-thickness dependence confirms that the redshift and spectral broadening occur when the effective metal thickness drops below the skin-depth limit. The electromagnetic field distribution illustrates the reduced field enhancement and reduced funneling effects near the gap area in the case of low plasma frequency, which is associated with reduced charge density in the metal film.

Keywords

References

  1. D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, "Metamaterial electromagnetic cloak at microwave frequencies," Sci. 314, 977-980 (2006). https://doi.org/10.1126/science.1133628
  2. J. B. Pendry, D. Schurig, and D. R. Smith, "Controlling electromagnetic fields," Sci. 312, 1780-1782 (2006). https://doi.org/10.1126/science.1125907
  3. J. B. Pendry, "Negative refraction makes a perfect lens," Phys. Rev. Lett. 85, 3966-3969 (2000). https://doi.org/10.1103/PhysRevLett.85.3966
  4. S. J. Park, J. T. Hong, S. J. Choi, H. S. Kim, W. K. Park, S. T. Han, J. Y. Park, S. Lee, D. S. Kim, and Y. H. Ahn, "Detection of microorganisms using terahertz metamaterials," Sci. Rep. 4, 4988 (2014).
  5. J. Federici and L. Moeller, "Review of terahertz and subterahertz wireless communications," J. Appl. Phys. 107, 111101 (2010). https://doi.org/10.1063/1.3386413
  6. K. Kawase, Y. Ogawa, Y. Watanabe, and H. Inoue, "Nondestructive terahertz imaging of illicit drugs using spectral fingerprints," Opt. Express 11, 2549-2554 (2003). https://doi.org/10.1364/OE.11.002549
  7. M. Tonouchi, "Cutting-edge terahertz technology," Nat. Photon. 1, 97-105 (2007). https://doi.org/10.1038/nphoton.2007.3
  8. A. Menikh, R. MacColl, C. A. Mannella, and X. C. Zhang, "Terahertz biosensing technology: Frontiers and progress," ChemPhysChem 3, 655-658 (2002). https://doi.org/10.1002/1439-7641(20020816)3:8<655::AID-CPHC655>3.0.CO;2-W
  9. R. M. Woodward, V. P. Wallace, D. D. Arnone, E. H. Linfield, and M. Pepper, "Terahertz pulsed imaging of skin cancer in the time and frequency domain," J. Biol. Phys. 29, 257-261 (2003). https://doi.org/10.1023/A:1024409329416
  10. S. J. Park, A. R. Kim, J. T. Hong, J. Y. Park, S. Lee, and Y. H. Ahn, "Crystallization kinetics of lead halide perovskite film monitored by in situ terahertz spectroscopy," J. Phys. Chem. Lett. 8, 401-406 (2017). https://doi.org/10.1021/acs.jpclett.6b02691
  11. C. Enkrich, M. Wegener, S. Linden, S. Burger, L. Zschiedrich, F. Schmidt, J. F. Zhou, T. Koschny, and C. M. Soukoulis, "Magnetic metamaterials at telecommunication and visible frequencies," Phys. Rev. Lett. 95, 203901 (2005). https://doi.org/10.1103/PhysRevLett.95.203901
  12. R. Marques, J. Martel, F. Mesa, and F. Medina, "Left-handed-media simulation and transmission of EM waves in subwavelength split-ring-resonator-loaded metallic waveguides," Phys. Rev. Lett. 89, 183901 (2002). https://doi.org/10.1103/PhysRevLett.89.183901
  13. H. O. Moser, B. D. F. Casse, O. Wilhelmi, and B. T. Saw, "Terahertz response of a microfabricated rod-split-ring-resonator electromagnetic metamaterial," Phys. Rev. Lett. 94, 4 (2005).
  14. C. Rockstuhl, T. Zentgraf, H. Guo, N. Liu, C. Etrich, I. Loa, K. Syassen, J. Kuhl, F. Lederer, and H. Giessen, "Resonances of split-ring resonator metamaterials in the near infrared," Appl. Phys. B: Lasers Opt. 84, 219-227 (2006). https://doi.org/10.1007/s00340-006-2205-2
  15. J. T. Hong, D. J. Park, J. H. Yim, J. K. Park, J. Y. Park, S. Lee, and Y. H. Ahn, "Dielectric constant engineering of single-walled carbon nanotube films for metamaterials and plasmonic devices," J. Phys. Chem. Lett. 4, 3950-3957 (2013). https://doi.org/10.1021/jz4020053
  16. H. T. Chen, W. J. Padilla, J. M. O. Zide, A. C. Gossard, A. J. Taylor, and R. D. Averitt, "Active terahertz metamaterial devices," Nat. 444, 597-600 (2006). https://doi.org/10.1038/nature05343
  17. H. T. Chen, J. F. O'Hara, A. K. Azad, A. J. Taylor, R. D. Averitt, D. B. Shrekenhamer, and W. J. Padilla, "Experimental demonstration of frequency-agile terahertz metamaterials," Nat. Photon. 2, 295-298 (2008). https://doi.org/10.1038/nphoton.2008.52
  18. S. B. Choi, J. S. Kyoung, H. S. Kim, H. R. Park, D. J. Park, B. J. Kim, Y. H. Ahn, F. Rotermund, H. T. Kim, K. J. Ahn, and D. S. Kim, "Nanopattern enabled terahertz all-optical switching on vanadium dioxide thin film," Appl. Phys. Lett. 98, 071105 (2011). https://doi.org/10.1063/1.3553504
  19. J. T. Hong, D. J. Park, J. Y. Moon, S. B. Choi, J. K. Park, F. Rotermund, J. Y. Park, S. Lee, and Y. H. Ahn, "Terahertz wave applications of single-walled carbon nanotube films with high shielding effectiveness," Appl. Phys. Express 5, 3 (2012).
  20. J. T. Hong, S. J. Park, J. Y. Park, S. Lee, and Y. H. Ahn, "Terahertz slot antenna devices fabricated on silver nanowire network films," Opt. Mater. Express 7, 1679-1685 (2017). https://doi.org/10.1364/OME.7.001679
  21. D. J. Park, S. J. Park, I. Park, and Y. H. Ahn, "Dielectric substrate effect on the metamaterial resonances in terahertz frequency range," Curr. Appl. Phys. 14, 570-574 (2014). https://doi.org/10.1016/j.cap.2014.01.015
  22. S. J. Park and Y. H. Ahn, "Substrate effects on terahertz metamaterial resonances for various metal thicknesses," J. Korean Phys. Soc. 65, 1843-1847 (2014). https://doi.org/10.3938/jkps.65.1843
  23. R. Singh, E. Smirnova, A. J. Taylor, J. F. O'Hara, and W. Zhang, "Optically thin terahertz metamaterials," Opt. Express 16, 6537-6543 (2008). https://doi.org/10.1364/OE.16.006537
  24. H. Guo, N. Liu, L. Fu, H. Schweizer, S. Kaiser, and H. Giessen, "Thickness dependence of the optical properties of split-ring resonator metamaterials," Phys. Status Solidi B 244, 1256-1261 (2007). https://doi.org/10.1002/pssb.200674515
  25. J. H. Kang, D. S. Kim, and M. Seo, "Terahertz wave interaction with metallic nanostructures," Nanophotonics 7, 763-793 (2018). https://doi.org/10.1515/nanoph-2017-0093