Abstract

Based on a multimode interference (MMI) coupler in slot waveguide structures, an ultracompact wavelength demultiplexer operating at 1.30 and 1.55μm wavelengths is proposed and designed by using a full-vector mapped Galerkin mode solver and a modified three-dimensional full-vector beam propagation method. The tapered waveguide structures are applied to connect the input/output channels and the MMI section for reducing excess loss. The modal characteristics of the slot waveguides are analyzed and the evolution of the injected field in whole device are demonstrated. The results show that a MMI section of 119.8μm in length, which is only 27.5% length of that of the MMI coupler by using conventional rib waveguides, is achieved with the contrasts of 26.03 and 28.14dB at wavelengths 1.30 and 1.55μm, respectively, and the insertion losses are below 0.2dB at both wavelengths.

© 2007 Optical Society of America

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References

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  1. C. A. Brackett, “Dense wavelength division multiplexing networks: Principles and applications,” IEEE J. Sel. Areas Commun. 8, 948–964 (1990).
    [Crossref]
  2. N. Goto and G. L. Yip, “Y-branch wavelength multi-demultiplexer for λ=1.30μm and 1.55μm,” Electron. Lett. 26, 102–103 (1990).
    [Crossref]
  3. A. Tervonen, P. Poyhonen, S. Honkanen, and M. Tahkokorpi, “A guided-wave Mach-Zehnder interferometer structure for wavelength multiplexing,” IEEE Photon. Technol. Lett. 3, 516–518 (1991).
    [Crossref]
  4. K. C. Lin and W. Y. Lee, “Guided-wave 1.30/1.55μm wavelength division multiplexer based on multimode interference,” Electron. Lett. 32, 1259–1261 (1996).
    [Crossref]
  5. B. Li, G. Li, E. Liu, Z. Jiang, J. Qin, and X. Wang, “Low-loss 1×2 multimode interference wavelength demultiplexer in silicon-germanium alloy,” IEEE Photon. Technol. Lett. 11, 575–577 (1999).
    [Crossref]
  6. S. L. Tsao, H. C. Guo, and C. W. Tsai, “A novel 1×2 single-mode 1300/1550nm wavelength division multiplexer with output facet-tilted MMI waveguide,” Opt. Commun. 232, 371–379 (2004).
    [Crossref]
  7. L. B. Soldano and E. C. M. Pennings, “Optical multimode interference devices based on self-imaging: principles and applications,” J. Lightwave Technol. 13, 615–627 (1995).
    [Crossref]
  8. R. Soref, “The past, present, and future of silicon photonics,” IEEE J. Sel. Top. Quantum Electron. 12, 1678–1687 (2006).
    [Crossref]
  9. B. Jalali and S. Fathpour, “Silicon photonics,” J. Lightwave Technol. 24, 4600–4615 (2006).
    [Crossref]
  10. V. R. Almeida, Q. Xu, C. A. barrios, and M. Lipson, “Guiding and confining light in void nanostructure,” Opt. Lett. 29, 1209–1211 (2004).
    [Crossref] [PubMed]
  11. Q. Xu, V. R. Almeida, R. R. Panepucci, and M. Lipson, “Experimental demonstration of guiding and confining in nanometer-size low-refractive index material,” Opt. Lett. 29, 1626–1628 (2004).
    [Crossref] [PubMed]
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    [Crossref] [PubMed]
  13. C. A. Barrios and M. Lipson, “electrically driven silicon resonant light emitting device based on slot-waveguide,” Opt. Express 13, 10092–10101 (2005).
    [Crossref] [PubMed]
  14. T. Fujisawa and M. Koshiba, “Polarization-independent optical directional coupler based on slot waveguides,” Opt. Lett. 31, 56–58 (2006).
    [Crossref] [PubMed]
  15. T. Fujisawa and M. Koshiba, “Theoretical Investigation of ultrasmall polarization-insensitive 1×2 multimode interference waveguides based on sandwiched structures,” IEEE Photon. Technol. Lett. 18, 1246–1248 (2006).
    [Crossref]
  16. T. Fujisasw and M. Koshiba, “All-optical logic gates based on nonlinear slot-waveguide coupler,” J. Opt. Soc. Am. B 23, 684–691(2006).
    [Crossref]
  17. F. Dell’Olio and V. M. N. Passaro, “Optical sensing by optimized silicon slot waveguides,” Opt. Express 15, 4977–4993 (2007).
    [Crossref] [PubMed]
  18. J. Xiao, X. Sun, and M. Zhang, “Vectorial analysis of optical waveguides by the mapped Galerkin method based on E fields,” J. Opt. Soc. Am. B 21, 798–805 (2004).
    [Crossref]
  19. J. Xiao and X. Sun, “A modified full-vectorial finite-difference beam propagation method based on H-fields for optical waveguides with step-index profiles,” Opt. Commun. 266, 505–511 (2006).
    [Crossref]
  20. W. P. Huang and C. L. Xu, “Simulation of three-dimensional optical waveguides by a full-vector beam propagation method,” IEEE J. Quantum Electron. 29, 2639–2649 (1993).
    [Crossref]
  21. G. R. Hadley, “Transparent boundary condition for the beam propagation method,” IEEE J. Quantum Electron. 28, 363–370 (1992).
    [Crossref]

2007 (1)

2006 (6)

R. Soref, “The past, present, and future of silicon photonics,” IEEE J. Sel. Top. Quantum Electron. 12, 1678–1687 (2006).
[Crossref]

T. Fujisawa and M. Koshiba, “Theoretical Investigation of ultrasmall polarization-insensitive 1×2 multimode interference waveguides based on sandwiched structures,” IEEE Photon. Technol. Lett. 18, 1246–1248 (2006).
[Crossref]

J. Xiao and X. Sun, “A modified full-vectorial finite-difference beam propagation method based on H-fields for optical waveguides with step-index profiles,” Opt. Commun. 266, 505–511 (2006).
[Crossref]

T. Fujisawa and M. Koshiba, “Polarization-independent optical directional coupler based on slot waveguides,” Opt. Lett. 31, 56–58 (2006).
[Crossref] [PubMed]

T. Fujisasw and M. Koshiba, “All-optical logic gates based on nonlinear slot-waveguide coupler,” J. Opt. Soc. Am. B 23, 684–691(2006).
[Crossref]

B. Jalali and S. Fathpour, “Silicon photonics,” J. Lightwave Technol. 24, 4600–4615 (2006).
[Crossref]

2005 (2)

2004 (4)

1999 (1)

B. Li, G. Li, E. Liu, Z. Jiang, J. Qin, and X. Wang, “Low-loss 1×2 multimode interference wavelength demultiplexer in silicon-germanium alloy,” IEEE Photon. Technol. Lett. 11, 575–577 (1999).
[Crossref]

1996 (1)

K. C. Lin and W. Y. Lee, “Guided-wave 1.30/1.55μm wavelength division multiplexer based on multimode interference,” Electron. Lett. 32, 1259–1261 (1996).
[Crossref]

1995 (1)

L. B. Soldano and E. C. M. Pennings, “Optical multimode interference devices based on self-imaging: principles and applications,” J. Lightwave Technol. 13, 615–627 (1995).
[Crossref]

1993 (1)

W. P. Huang and C. L. Xu, “Simulation of three-dimensional optical waveguides by a full-vector beam propagation method,” IEEE J. Quantum Electron. 29, 2639–2649 (1993).
[Crossref]

1992 (1)

G. R. Hadley, “Transparent boundary condition for the beam propagation method,” IEEE J. Quantum Electron. 28, 363–370 (1992).
[Crossref]

1991 (1)

A. Tervonen, P. Poyhonen, S. Honkanen, and M. Tahkokorpi, “A guided-wave Mach-Zehnder interferometer structure for wavelength multiplexing,” IEEE Photon. Technol. Lett. 3, 516–518 (1991).
[Crossref]

1990 (2)

C. A. Brackett, “Dense wavelength division multiplexing networks: Principles and applications,” IEEE J. Sel. Areas Commun. 8, 948–964 (1990).
[Crossref]

N. Goto and G. L. Yip, “Y-branch wavelength multi-demultiplexer for λ=1.30μm and 1.55μm,” Electron. Lett. 26, 102–103 (1990).
[Crossref]

Almeida, V. R.

Baehr-Jones, T.

Barrios, C. A.

Brackett, C. A.

C. A. Brackett, “Dense wavelength division multiplexing networks: Principles and applications,” IEEE J. Sel. Areas Commun. 8, 948–964 (1990).
[Crossref]

Dalton, L.

Dell’Olio, F.

Fathpour, S.

Fujisasw, T.

Fujisawa, T.

T. Fujisawa and M. Koshiba, “Polarization-independent optical directional coupler based on slot waveguides,” Opt. Lett. 31, 56–58 (2006).
[Crossref] [PubMed]

T. Fujisawa and M. Koshiba, “Theoretical Investigation of ultrasmall polarization-insensitive 1×2 multimode interference waveguides based on sandwiched structures,” IEEE Photon. Technol. Lett. 18, 1246–1248 (2006).
[Crossref]

Goto, N.

N. Goto and G. L. Yip, “Y-branch wavelength multi-demultiplexer for λ=1.30μm and 1.55μm,” Electron. Lett. 26, 102–103 (1990).
[Crossref]

Guo, H. C.

S. L. Tsao, H. C. Guo, and C. W. Tsai, “A novel 1×2 single-mode 1300/1550nm wavelength division multiplexer with output facet-tilted MMI waveguide,” Opt. Commun. 232, 371–379 (2004).
[Crossref]

Hadley, G. R.

G. R. Hadley, “Transparent boundary condition for the beam propagation method,” IEEE J. Quantum Electron. 28, 363–370 (1992).
[Crossref]

Hochberg, M.

Honkanen, S.

A. Tervonen, P. Poyhonen, S. Honkanen, and M. Tahkokorpi, “A guided-wave Mach-Zehnder interferometer structure for wavelength multiplexing,” IEEE Photon. Technol. Lett. 3, 516–518 (1991).
[Crossref]

Huang, W. P.

W. P. Huang and C. L. Xu, “Simulation of three-dimensional optical waveguides by a full-vector beam propagation method,” IEEE J. Quantum Electron. 29, 2639–2649 (1993).
[Crossref]

Jalali, B.

Jen, A. K. Y.

Jiang, Z.

B. Li, G. Li, E. Liu, Z. Jiang, J. Qin, and X. Wang, “Low-loss 1×2 multimode interference wavelength demultiplexer in silicon-germanium alloy,” IEEE Photon. Technol. Lett. 11, 575–577 (1999).
[Crossref]

Koshiba, M.

T. Fujisawa and M. Koshiba, “Theoretical Investigation of ultrasmall polarization-insensitive 1×2 multimode interference waveguides based on sandwiched structures,” IEEE Photon. Technol. Lett. 18, 1246–1248 (2006).
[Crossref]

T. Fujisasw and M. Koshiba, “All-optical logic gates based on nonlinear slot-waveguide coupler,” J. Opt. Soc. Am. B 23, 684–691(2006).
[Crossref]

T. Fujisawa and M. Koshiba, “Polarization-independent optical directional coupler based on slot waveguides,” Opt. Lett. 31, 56–58 (2006).
[Crossref] [PubMed]

Lawson, R.

Lee, W. Y.

K. C. Lin and W. Y. Lee, “Guided-wave 1.30/1.55μm wavelength division multiplexer based on multimode interference,” Electron. Lett. 32, 1259–1261 (1996).
[Crossref]

Li, B.

B. Li, G. Li, E. Liu, Z. Jiang, J. Qin, and X. Wang, “Low-loss 1×2 multimode interference wavelength demultiplexer in silicon-germanium alloy,” IEEE Photon. Technol. Lett. 11, 575–577 (1999).
[Crossref]

Li, G.

B. Li, G. Li, E. Liu, Z. Jiang, J. Qin, and X. Wang, “Low-loss 1×2 multimode interference wavelength demultiplexer in silicon-germanium alloy,” IEEE Photon. Technol. Lett. 11, 575–577 (1999).
[Crossref]

Liao, Y.

Lin, K. C.

K. C. Lin and W. Y. Lee, “Guided-wave 1.30/1.55μm wavelength division multiplexer based on multimode interference,” Electron. Lett. 32, 1259–1261 (1996).
[Crossref]

Lipson, M.

Liu, E.

B. Li, G. Li, E. Liu, Z. Jiang, J. Qin, and X. Wang, “Low-loss 1×2 multimode interference wavelength demultiplexer in silicon-germanium alloy,” IEEE Photon. Technol. Lett. 11, 575–577 (1999).
[Crossref]

Panepucci, R. R.

Passaro, V. M. N.

Pennings, E. C. M.

L. B. Soldano and E. C. M. Pennings, “Optical multimode interference devices based on self-imaging: principles and applications,” J. Lightwave Technol. 13, 615–627 (1995).
[Crossref]

Poyhonen, P.

A. Tervonen, P. Poyhonen, S. Honkanen, and M. Tahkokorpi, “A guided-wave Mach-Zehnder interferometer structure for wavelength multiplexing,” IEEE Photon. Technol. Lett. 3, 516–518 (1991).
[Crossref]

Qin, J.

B. Li, G. Li, E. Liu, Z. Jiang, J. Qin, and X. Wang, “Low-loss 1×2 multimode interference wavelength demultiplexer in silicon-germanium alloy,” IEEE Photon. Technol. Lett. 11, 575–577 (1999).
[Crossref]

Scherer, A.

Soldano, L. B.

L. B. Soldano and E. C. M. Pennings, “Optical multimode interference devices based on self-imaging: principles and applications,” J. Lightwave Technol. 13, 615–627 (1995).
[Crossref]

Soref, R.

R. Soref, “The past, present, and future of silicon photonics,” IEEE J. Sel. Top. Quantum Electron. 12, 1678–1687 (2006).
[Crossref]

Sullivan, P. A.

Sun, X.

J. Xiao and X. Sun, “A modified full-vectorial finite-difference beam propagation method based on H-fields for optical waveguides with step-index profiles,” Opt. Commun. 266, 505–511 (2006).
[Crossref]

J. Xiao, X. Sun, and M. Zhang, “Vectorial analysis of optical waveguides by the mapped Galerkin method based on E fields,” J. Opt. Soc. Am. B 21, 798–805 (2004).
[Crossref]

Tahkokorpi, M.

A. Tervonen, P. Poyhonen, S. Honkanen, and M. Tahkokorpi, “A guided-wave Mach-Zehnder interferometer structure for wavelength multiplexing,” IEEE Photon. Technol. Lett. 3, 516–518 (1991).
[Crossref]

Tervonen, A.

A. Tervonen, P. Poyhonen, S. Honkanen, and M. Tahkokorpi, “A guided-wave Mach-Zehnder interferometer structure for wavelength multiplexing,” IEEE Photon. Technol. Lett. 3, 516–518 (1991).
[Crossref]

Tsai, C. W.

S. L. Tsao, H. C. Guo, and C. W. Tsai, “A novel 1×2 single-mode 1300/1550nm wavelength division multiplexer with output facet-tilted MMI waveguide,” Opt. Commun. 232, 371–379 (2004).
[Crossref]

Tsao, S. L.

S. L. Tsao, H. C. Guo, and C. W. Tsai, “A novel 1×2 single-mode 1300/1550nm wavelength division multiplexer with output facet-tilted MMI waveguide,” Opt. Commun. 232, 371–379 (2004).
[Crossref]

Wang, G.

Wang, X.

B. Li, G. Li, E. Liu, Z. Jiang, J. Qin, and X. Wang, “Low-loss 1×2 multimode interference wavelength demultiplexer in silicon-germanium alloy,” IEEE Photon. Technol. Lett. 11, 575–577 (1999).
[Crossref]

Xiao, J.

J. Xiao and X. Sun, “A modified full-vectorial finite-difference beam propagation method based on H-fields for optical waveguides with step-index profiles,” Opt. Commun. 266, 505–511 (2006).
[Crossref]

J. Xiao, X. Sun, and M. Zhang, “Vectorial analysis of optical waveguides by the mapped Galerkin method based on E fields,” J. Opt. Soc. Am. B 21, 798–805 (2004).
[Crossref]

Xu, C. L.

W. P. Huang and C. L. Xu, “Simulation of three-dimensional optical waveguides by a full-vector beam propagation method,” IEEE J. Quantum Electron. 29, 2639–2649 (1993).
[Crossref]

Xu, Q.

Yip, G. L.

N. Goto and G. L. Yip, “Y-branch wavelength multi-demultiplexer for λ=1.30μm and 1.55μm,” Electron. Lett. 26, 102–103 (1990).
[Crossref]

Zhang, M.

Electron. Lett. (2)

N. Goto and G. L. Yip, “Y-branch wavelength multi-demultiplexer for λ=1.30μm and 1.55μm,” Electron. Lett. 26, 102–103 (1990).
[Crossref]

K. C. Lin and W. Y. Lee, “Guided-wave 1.30/1.55μm wavelength division multiplexer based on multimode interference,” Electron. Lett. 32, 1259–1261 (1996).
[Crossref]

IEEE J. Quantum Electron. (2)

W. P. Huang and C. L. Xu, “Simulation of three-dimensional optical waveguides by a full-vector beam propagation method,” IEEE J. Quantum Electron. 29, 2639–2649 (1993).
[Crossref]

G. R. Hadley, “Transparent boundary condition for the beam propagation method,” IEEE J. Quantum Electron. 28, 363–370 (1992).
[Crossref]

IEEE J. Sel. Areas Commun. (1)

C. A. Brackett, “Dense wavelength division multiplexing networks: Principles and applications,” IEEE J. Sel. Areas Commun. 8, 948–964 (1990).
[Crossref]

IEEE J. Sel. Top. Quantum Electron. (1)

R. Soref, “The past, present, and future of silicon photonics,” IEEE J. Sel. Top. Quantum Electron. 12, 1678–1687 (2006).
[Crossref]

IEEE Photon. Technol. Lett. (3)

B. Li, G. Li, E. Liu, Z. Jiang, J. Qin, and X. Wang, “Low-loss 1×2 multimode interference wavelength demultiplexer in silicon-germanium alloy,” IEEE Photon. Technol. Lett. 11, 575–577 (1999).
[Crossref]

A. Tervonen, P. Poyhonen, S. Honkanen, and M. Tahkokorpi, “A guided-wave Mach-Zehnder interferometer structure for wavelength multiplexing,” IEEE Photon. Technol. Lett. 3, 516–518 (1991).
[Crossref]

T. Fujisawa and M. Koshiba, “Theoretical Investigation of ultrasmall polarization-insensitive 1×2 multimode interference waveguides based on sandwiched structures,” IEEE Photon. Technol. Lett. 18, 1246–1248 (2006).
[Crossref]

J. Lightwave Technol. (2)

L. B. Soldano and E. C. M. Pennings, “Optical multimode interference devices based on self-imaging: principles and applications,” J. Lightwave Technol. 13, 615–627 (1995).
[Crossref]

B. Jalali and S. Fathpour, “Silicon photonics,” J. Lightwave Technol. 24, 4600–4615 (2006).
[Crossref]

J. Opt. Soc. Am. B (2)

Opt. Commun. (2)

J. Xiao and X. Sun, “A modified full-vectorial finite-difference beam propagation method based on H-fields for optical waveguides with step-index profiles,” Opt. Commun. 266, 505–511 (2006).
[Crossref]

S. L. Tsao, H. C. Guo, and C. W. Tsai, “A novel 1×2 single-mode 1300/1550nm wavelength division multiplexer with output facet-tilted MMI waveguide,” Opt. Commun. 232, 371–379 (2004).
[Crossref]

Opt. Express (3)

Opt. Lett. (3)

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Figures (5)

Fig. 1.
Fig. 1.

(a). Schematic of an ultracompact wavelength demultiplexer based on the MMI coupler and (b) cross section of a slot waveguide

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Fig. 2.
Fig. 2.

Field patterns of the quasi-TM fundamental mode for a slot waveguide: (a) major component Ey and (b) minor component Ex

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Fig. 3.
Fig. 3.

Beat lengths and their ratio as functions of (a) the width of slot waveguide W MMI and (b) the height of slot region hs

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Fig. 4.
Fig. 4.

Contrast, (a) and (c), and insert losses, (b) and (d), of the demultiplexer as functions of the width of W MMI, (a) and (b), and length of the L MMI, (c) and (d)

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Fig. 5.
Fig. 5.

Field distributions in the proposed wavelength demultiplexer with W MMI=3.0μm and L MMI=119.8μm: (a) λ=1.30μm and (b) λ=1.55μm

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Equations (17)

Equations on this page are rendered with MathJax. Learn more.

2 j k 0 n ¯ ∂ ∂ z [ E x E y ] = [ A xx x + A xx y A xy A yx A yy x + A yy y ] [ E x E y ]
A xx x E x = ∂ ∂ x [ 1 n 2 ∂ ∂ x ( n 2 E x ) ] + 1 2 k 0 2 ( n 2 − n ¯ 2 ) E x
A xx y E x = ∂ 2 E x ∂ y 2 + 1 2 k 0 2 ( n 2 − n ¯ 2 ) E x
A xy u y = ∂ ∂ x [ 1 n 2 ∂ ∂ y ( n 2 E y ) ] − ∂ 2 ∂ x ∂ y E y
A yy x E y = ∂ 2 E y ∂ x 2 + 1 2 k 0 2 ( n 2 − n ¯ 2 ) E y
A yy y E y = ∂ ∂ y [ 1 n 2 ∂ ∂ y ( n 2 E y ) ] + 1 2 k 0 2 ( n 2 − n ¯ 2 ) E y
A yx E x = ∂ ∂ y [ 1 n 2 ∂ ∂ x ( n 2 E x ) ] − ∂ 2 ∂ x ∂ y E x
A xy E y = 1 4 Δ x Δ y [ ( a 1 − 1 ) E y p + 1 , q + 1 , l − ( a 2 − 1 ) E y p + 1 , q − 1 , l − ( a 3 − 1 ) E y p − 1 , q + 1 , l + ( a 4 − 1 ) E y p − 1 , q − 1 , l + ( b 1 − b 2 ) E y p , q + 1 , l + ( b 3 − b 4 ) E y p , q − 1 , l ]
a 1 = 2 n p + 1 , q + 1 2 n p , q 2 + n p + 1 , q 2 and a 2 = 2 n p + 1 , q − 1 2 n p , q 2 + n p + 1 , q 2
a 3 = 2 n p − 1 , q + 1 2 n p , q 2 + n p − 1 , q 2 and a 4 = 2 n p − 1 , q − 1 2 n p , q 2 + n p − 1 , q 2
b 1 = 2 n p , q + 1 2 n p , q 2 + n p + 1 , q 2 and b 2 = 2 n p , q − 1 2 n p , q 2 + n p − 1 , q 2
b 3 = 2 n p , q − 1 2 n p , q 2 + n p − 1 , q 2 and b 4 = 2 n p , q − 1 2 n p , q 2 + n p + 1 , q 2
L π = π β 0 − β 1
L MMI = p L π λ 1 = ( p + q ) L π λ 2
119.5 μm = 5 L π λ 1 ≈ 6 L π λ 2 = 119.8 μm
C = 10 log ⁡ 10 ( P 1 P 2 )
L = − 10 log ⁡ 10 ( P 1 P i )

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