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Plasmonics

, Volume 4, Issue 2, pp 141–146 | Cite as

Modulation of Main Lobe for Superfocusing Using Subwavelength Metallic Heterostructures

  • Yongqi FuEmail author
  • Wei Zhou
Article

Abstract

A subwavelength metallic heterostructure is put forth for the purpose of suppressing sidelobes and improving superfocusing at a quasi-far field region. Improvement has been made by means of optimization of the heterostructure composed of structured Au and Ag thin films. By tuning thicknesses of both the structured Au and Ag films, we can modulate propagation distance of the plasmonic lens and beam width of main lobe for the superfocusing. A finite-difference and time-domain (FDTD) algorithm-based computational numerical calculation was carried out for analyzing the focusing performance and tuning ability of the metal films. Our computational calculation results show that the sidelobes which play negative role for the focusing can be suppressed significantly in the case of the metal film thicknesses of h Au = 50 nm and h Ag = 10 nm. Theoretically, the metallic structure with smaller thicknesses of the structured Au and Ag films is helpful for improving the focusing performance. This heterostructure-based device is possible to be used as a superlens or nanoprobe in data storage, nanometrology/inspection, and biosensing etc.

Keywords

Heterostructure Superfocusing FDTD Main lobe Sidelobes 

Notes

Acknowledgement

The work was supported by the National Natural Science Foundation of China (No.60877021) and “Distinguished Talent Program” from University of Electronic Science and Technology of China (No. 08JC00401). The authors acknowledge the financial support from A*STAR (Agency for Science, Technology and Research), Singapore, through the project on “Novel optical nanoprobe for nanometrology based on surface plasmon polaritons” (SERC Grant No. 072 101 0023).

References

  1. 1.
    Levy U, Abashin M, Ikeda K, Krishnamoorthy A, Cunningham J, Fainman Y (2007) Phys Rev Lett 98:243901 doi: 10.1103/PhysRevLett.98.243901 CrossRefGoogle Scholar
  2. 2.
    Wang B, Wang GP (2006) Appl Phys Lett 88:013114 doi: 10.1063/1.2161021 CrossRefGoogle Scholar
  3. 3.
    Martin-Moreno L, García-Vidal FJ, Lezec HJ, Degiron A, Ebbesen TW (2003) Phys Rev Lett 90:167401 doi: 10.1103/PhysRevLett.90.167401 CrossRefGoogle Scholar
  4. 4.
    Ebbesen TW, Lezec HJ, Ghaemi HF, Thio T, Wolff PA (1998) Nature 39:667–669 doi: 10.1038/35570 CrossRefGoogle Scholar
  5. 5.
    Huang L, Hegg MC, Wang C-J, Lin LY (2007) Micro Nano Letters. IET 2:103CrossRefGoogle Scholar
  6. 6.
    Lee J, Kim J (2008) Quantum Electronics and Laser Science Conference (QELS). San Jose, California: May 4, p.QTuD6Google Scholar
  7. 7.
    Ting X, Wang C, Du C, Luo X (2008) Opt Express 16:4753 doi: 10.1364/OE.16.004753 CrossRefGoogle Scholar
  8. 8.
    Reuven G, Sinton D, Kavanagh KL, Brolo AG (2008) Chem A Res 41:1049CrossRefGoogle Scholar
  9. 9.
    De M, Ghosh PS, Rotello VM (2008) Adv Mater 20:1 doi: 10.1002/adma.200703183 CrossRefGoogle Scholar
  10. 10.
    Fang N, Lee H, Sun C, Zhang X (2005) Science 308:534 doi: 10.1126/science.1108759 CrossRefGoogle Scholar
  11. 11.
    Zhang X, Liu Z (2008) Nat Mater 7:435 doi: 10.1038/nmat2141 CrossRefGoogle Scholar
  12. 12.
    Liu Z, Steele JM, Srituravanich W, Pikus Y, Sun C, Zhang X (2005) Nano Lett 5:1726 doi: 10.1021/nl051013j CrossRefGoogle Scholar
  13. 13.
    Fu Y, Zhou W, Lennie LEN, Du C, Luo X (2007) Appl Phys Lett 91(6):061124 doi: 10.1063/1.2769942 CrossRefGoogle Scholar
  14. 14.
    Liu Z, Steele JM, Srituravanich W, Pikus Y, Sun C, Zhang X (2005) Nano Lett 5:1726 doi: 10.1021/nl051013j CrossRefGoogle Scholar
  15. 15.
    Fu Y, Zhou W, Lennie LEN (2008) Res Lett Phys 2008:148085Google Scholar
  16. 16.
    Nastasi M, Mayer JW, Hirvonen JK (eds) (1996) Ion–solid interactions: fundamentals and applications. Cambridge University Press, Cambridge, p 267Google Scholar
  17. 17.
    Jhonson PB, Christy RW (1972) Phys Rev B 6:4370 doi: 10.1103/PhysRevB.6.4370 CrossRefGoogle Scholar
  18. 18.
    Belotelov VI, Carotenuto G, Nicolais L, Pepe GP, Zvezdin AK (2005) Eur Phys J B 45:317 doi: 10.1140/epjb/e2005-00203-7 CrossRefGoogle Scholar
  19. 19.
    Rhodes WT (ed) (2007) Surface Plasmon Nanophtonics. Springer, Berlin, p.28–37Google Scholar

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.School of Physical ElectronicsUniversity of Electronic Science and Technology of ChinaChengduPeople’s Republic of China
  2. 2.Precision Engineering and Nanotechnology Centre, School of Mechanical and Aerospace EngineeringNanyang Technological UniversitySingaporeSingapore

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