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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 16, Iss. 17 — Aug. 18, 2008
  • pp: 12677–12687

Vertical coupling between gap plasmon waveguides

Galen B. Hoffman and Ronald M. Reano  »View Author Affiliations

Optics Express, Vol. 16, Issue 17, pp. 12677-12687 (2008)

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This work examines vertical coupling between gap plasmon waveguides for use in high confinement power transfer and power splitting applications at 1.55 µm free space wavelength. The supermode interference method is used to obtain key coupler performance parameters such as coupling length, extinction ratio, net coupled output power, radiated power, and reflected power as a function of waveguide center-to-center spacing, core refractive index, and gap width. The initial power distribution among the two coupler supermodes is obtained via the mode matching method for a single input waveguide feed. Excellent agreement with three-dimensional finite difference time domain simulations is observed for the case of square 50 nm gaps with core refractive indices of 2.50 and a center-to-center spacing of 112 nm. Local maxima in the net coupled output power are found to coincide with local minima in the coupling length. An increase in the core refractive index from 1.00 to 2.5 increases the local maximum net coupled output power from 6.4% to 49% but decreases the extinction ratio from 12.7 to 6.94. A sweep of the width of the core from 25 to 100 nm increases the net coupled output power from 43.7% to 52.0%, but increases the coupling length from 1.58 to 3.19 µm and decreases the extinction ratio from 7.39 to 6.57.

© 2008 Optical Society of America

OCIS Codes
(130.1750) Integrated optics : Components
(130.2790) Integrated optics : Guided waves
(130.3120) Integrated optics : Integrated optics devices
(250.5403) Optoelectronics : Plasmonics

ToC Category:
Integrated Optics

Original Manuscript: July 14, 2008
Revised Manuscript: August 4, 2008
Manuscript Accepted: August 5, 2008
Published: August 6, 2008

Galen B. Hoffman and Ronald M. Reano, "Vertical coupling between gap plasmon waveguides," Opt. Express 16, 12677-12687 (2008)

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  1. J. A. Conway, S. Sahni, and T. Szkopek, "Plasmonic interconnects versus conventional interconnects: a comparison of latency, cross-talk and energy costs," Opt. Express 15, 4474 - 4484 (2007). [CrossRef] [PubMed]
  2. K. Jung, F. L. Teixeira, and R. M. Reano, "Au/SiO2 nanoring plasmon waveguides at optical communication band," IEEE J. Lightwave Tech. 25, 2757 - 2765 (2007). [CrossRef]
  3. P. Berini, "Air gaps in metal stripe waveguides supporting long-range surface plasmon polaritons," J. Appl. Phys. 102, 33112 (2007). [CrossRef]
  4. G. Veronis and S. Fan, "Guided subwavelength plasmonic mode supported by a slot in a thin metal film," Opt. Lett. 30, 3359 - 3361 (2005). [CrossRef]
  5. L. Chen, J. Shakya, and M. Lipson, "Subwavelength confinement in an integrated metal slot waveguide on silicon," Opt. Lett. 31, 2133 - 2135 (2006). [CrossRef] [PubMed]
  6. D. Gramotnev, "Adiabatic nanofocusing of plasmons by sharp metallic grooves: Geometrical optics approach," J. Appl. Phys. 98, 104302 (2005). [CrossRef]
  7. R. Buckley and P. Berini, "Figures of merit for 2D surface plasmon waveguides and application to metal stripes," Opt. Express 15, 12174 - 12182 (2007). [CrossRef] [PubMed]
  8. P. Berini, "Plasmon-polariton waves guided by thin lossy metal films of finite width: Bound modes of symmetric structures," Phys. Rev. B 61, 10484 - 10503 (2000). [CrossRef]
  9. R. Zia, J. A. Schuller, A. Chandran, and M. L. Brongersma, "Plasmonics: the next chip-scale technology," Mat. Today 9, 20 - 27 (2006). [CrossRef]
  10. S. I. Bozhevolnyi, V. S. Volkov, E. Devaux, and T. W. Ebbesen, "Channel plasmon-polariton guiding by subwavelength metal grooves," Phys. Rev. Lett. 95, 46802 (2005). [CrossRef]
  11. M. Yan and M. Qiu, "Guided plasmon polariton at 2D metal corners," J. Opt. Soc. Am. B 24, 2333 - 2342 (2007). [CrossRef]
  12. G. Veronis and S. Fan, "Modes of subwavelength plasmonic slot waveguides," IEEE J. Lightwave Tech. 25, 2511 - 2521 (2007). [CrossRef]
  13. G. Veronis and S. Fan, "Crosstalk between three-dimensional plasmonic slot waveguides," Opt. Express 16, 2129 - 2140 (2008). [CrossRef] [PubMed]
  14. H. S. Won, K. C. Kim, S. H. Song, C. Oh, P. S. Kim, S. Park, and S. Kim, "Vertical coupling of long-range surface plasmon polaritons," Appl. Phys. Lett. 88, 11110 (2006). [CrossRef]
  15. J. A. Pereda, A. Vegas, and A. Prieto, "An improved compact 2D full-wave FDFD method for general guided wave structures," Microwave Opt. Technol. Lett. 38, 331 - 335 (2003). [CrossRef]
  16. http://www.comsol.com
  17. H. J. Hagemann, W. Gudat, and C. Kunz, "Optical constants from the far infrared to the x-ray region: Mg, Al, Cu, Ag, Au, Bi, C, and Al2O3," J. Opt. Soc. Am. 65, 742-744 (1975). [CrossRef]
  18. R. M. Reano and S. W. Pang, "Sealed three-dimensional nanochannels," J. Vac. Sci. Technol. B 23, 2995 - 2999 (2005). [CrossRef]
  19. Bruce McConnel, "Using self-assembly to create airgap microprocessors" (IBM, 2007), http://www-03.ibm.com/press/us/en/presskit/21463.wss, Accessed 10-30-07.
  20. D. F. P. Pile, D. K. Gramotnev, M. Haraguchi, T. Okamoto, and M. Fukui, "Numerical analysis of coupled wedge plasmons in a structure of two metal wedges separated by a gap," J. Appl. Phys. 100, 13101 (2006). [CrossRef]
  21. K. Okamoto, Fundamentals of Optical Waveguides, (Academic Press, 2006).
  22. C. Pollock, Fundamentals of Optoelectronics, (Ceramic Book and Literature Service, 2003), Chap. 11.
  23. W. C. Chew, Waves and Fields in Inhomogeneous Media, (IEEE Press, 1995), Chap. 6.
  24. D. Marcuse, Light Transmission Optics, (Van Norstrand Reinhold Company, 1972), pp. 322-326.
  25. G. Strang, Linear Algebra and Its Applications 3rd Ed., (Thomson Learning, 1988), pp. 448 - 449.
  26. R. Zia, M. D. Selker, P. B. Catrysse, and M. L. Brongersma, "Geometries and materials for subwavelength surface plasmon modes," J. Opt. Soc. Am. A. 21, 2442 - 2446 (2004). [CrossRef]
  27. S. Collin, F. Pardo, and J. Pelouard, "Waveguiding in nanoscale metallic apertures," Opt. Express 15, 4310 - 4320 (2007). [CrossRef] [PubMed]
  28. http://www.rsoftdesign.com

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