Abstract

The length of a directional coupler, including the straight and curved parts, is strongly polarization dependent, especially for use in waveguide tap monitoring applications. Three types of curved structure in the coupled regions are presented to demonstrate the different phase contributions in a directional coupler. A 12μm thick silicon-on-insulator waveguide single-mode region was theoretically verified by using the beam propagation method, thereby significantly improving the polarization dependence and coupling loss with a conventional fiber. The Mach–Zehnder directional coupler made of a 12μm thick silicon-on-insulator waveguide could minimize the severe polarization dependence on the optical tap port and achieve a flattened wavelength response by implementing the coupled phase effect from the directional coupler’s curved structures. The results demonstrated that the optical waveguide tap port, carrying a portion of the light signal, showed a 0.024 coupling ratio and 0.3dB for the polarization-dependent loss at a 1550nm wavelength. The wavelength variation in the tap splitting ratio and polarization was less than 1% and 0.6dB, respectively, across the entire C-band. A 0.26dB per interface coupling loss was also achieved between the 12μm thick silicon-on-insulator waveguide and SMF-28 fiber.

© 2010 Optical Society of America

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  1. C. A. Al Sayeed, A. Vukovic, O. W. W. Yang, and Heng Hua, “Low-loss reconfigurable OADM for metro core optical network,” IET Optoelectron. 1, 178—184 (2007).
    [CrossRef]
  2. S. H. Hsu, “Polarization-dependent loss compensation on silicon-wire waveguide tap by complex refractive index of metals,” Opt. Lett. 34,1798—1800 (2009).
    [CrossRef] [PubMed]
  3. G. B. Cao, F. Gao, J. Jiang, and F. Zhang, “Directional couplers realized on silicon-on-insulator,” IEEE Photon. Technol. Lett. 17, 1671–1673 (2005).
    [CrossRef]
  4. A. Yariv and P. Yeh, Photonics: Optical Electronics in Modern Communications, 6th ed. (Oxford Univ. Press, 2007), Chap. 13.
  5. K. Jinguji, N. Takato, A. Sugita, and M. Kawachi, “Mach–Zehnder interferometer type optical waveguide coupler with wavelength-flattened coupling ratio,” Electron. Lett. 26, 1326–1327 (1990).
    [CrossRef]
  6. B. E. Little and T. Murphy, “Design rules for maximally flat wavelength-insensitive optical power dividers using Mach–Zehnder structures,” IEEE Photon. Technol. Lett. 9, 1607–1609 (1997).
    [CrossRef]
  7. J.-M. Liu, Photonic Devices (Cambridge Univ. Press, 2005), Chap. 5.
    [CrossRef]
  8. D. Yevick and B. Hermansson, “New formulations of the matrix beam propagation method: application to rib waveguides,” IEEE J. Quantum Electron. 25,221–229 (1989).
    [CrossRef]
  9. S. Jungling and J. C. Chen, “A study and optimization of eigenmode calculations using the imaginary-distance beam-propagation method,” IEEE J. Quantum Electron. 30,2098–2105 (1994).
    [CrossRef]
  10. G. R. Hadley and R. E. Smith, “Full-vector waveguide modeling using an iterative finite-difference method with transparent boundary conditions,” J. Lightwave Technol. 13,465–469 (1995).
    [CrossRef]
  11. S. H. Hsu, “A 5 μm-thick SOI waveguide with low birefringence and low roughness and optical interconnection using high numerical aperture fiber,” IEEE Photon. Technol. Lett. 20,1003—1005 (2008).
    [CrossRef]
  12. S.-H. Hsu and Y.-L. Tsai, “Tapping signal power on 12 μm-thick SOI optical waveguide for performance monitoring,” Electron. Lett. 45(3),161–163 (2009).
    [CrossRef]
  13. Y. P. Li and C. H. Henry, “Silica-based optical integrated circuits,” IEE Proc.: Optoelectron. 143,263–280 (1996).
    [CrossRef]
  14. S. Pogossian, L. Vescan, and A. Vonsovici, “The single mode condition for semiconductor rib waveguides with large cross-section,” J. Lightwave Technol. 16,1851–1853 (1998).
    [CrossRef]
  15. O. Powell, “Single-mode condition for silicon rib waveguides,” J. Lightwave Technol. 20,1851–1855 (2002).
    [CrossRef]
  16. R. A. Soref, J. Schmidtchen, and K. Petermann, “Large single-mode rib waveguides in Ge-Si-Si and Si-on-SiO2,” IEEE J. Quantum Electron. 27,1971–1974 (1991).
    [CrossRef]
  17. G. T. Reed and A. P. Knights, Silicon Photonics—an IntroductionWiley, 2004), Chap. 4.
    [CrossRef]

2009

S. H. Hsu, “Polarization-dependent loss compensation on silicon-wire waveguide tap by complex refractive index of metals,” Opt. Lett. 34,1798—1800 (2009).
[CrossRef] [PubMed]

S.-H. Hsu and Y.-L. Tsai, “Tapping signal power on 12 μm-thick SOI optical waveguide for performance monitoring,” Electron. Lett. 45(3),161–163 (2009).
[CrossRef]

2008

S. H. Hsu, “A 5 μm-thick SOI waveguide with low birefringence and low roughness and optical interconnection using high numerical aperture fiber,” IEEE Photon. Technol. Lett. 20,1003—1005 (2008).
[CrossRef]

2007

C. A. Al Sayeed, A. Vukovic, O. W. W. Yang, and Heng Hua, “Low-loss reconfigurable OADM for metro core optical network,” IET Optoelectron. 1, 178—184 (2007).
[CrossRef]

2005

G. B. Cao, F. Gao, J. Jiang, and F. Zhang, “Directional couplers realized on silicon-on-insulator,” IEEE Photon. Technol. Lett. 17, 1671–1673 (2005).
[CrossRef]

2002

1998

1997

B. E. Little and T. Murphy, “Design rules for maximally flat wavelength-insensitive optical power dividers using Mach–Zehnder structures,” IEEE Photon. Technol. Lett. 9, 1607–1609 (1997).
[CrossRef]

1996

Y. P. Li and C. H. Henry, “Silica-based optical integrated circuits,” IEE Proc.: Optoelectron. 143,263–280 (1996).
[CrossRef]

1995

G. R. Hadley and R. E. Smith, “Full-vector waveguide modeling using an iterative finite-difference method with transparent boundary conditions,” J. Lightwave Technol. 13,465–469 (1995).
[CrossRef]

1994

S. Jungling and J. C. Chen, “A study and optimization of eigenmode calculations using the imaginary-distance beam-propagation method,” IEEE J. Quantum Electron. 30,2098–2105 (1994).
[CrossRef]

1991

R. A. Soref, J. Schmidtchen, and K. Petermann, “Large single-mode rib waveguides in Ge-Si-Si and Si-on-SiO2,” IEEE J. Quantum Electron. 27,1971–1974 (1991).
[CrossRef]

1990

K. Jinguji, N. Takato, A. Sugita, and M. Kawachi, “Mach–Zehnder interferometer type optical waveguide coupler with wavelength-flattened coupling ratio,” Electron. Lett. 26, 1326–1327 (1990).
[CrossRef]

1989

D. Yevick and B. Hermansson, “New formulations of the matrix beam propagation method: application to rib waveguides,” IEEE J. Quantum Electron. 25,221–229 (1989).
[CrossRef]

Al Sayeed, C. A.

C. A. Al Sayeed, A. Vukovic, O. W. W. Yang, and Heng Hua, “Low-loss reconfigurable OADM for metro core optical network,” IET Optoelectron. 1, 178—184 (2007).
[CrossRef]

Cao, G. B.

G. B. Cao, F. Gao, J. Jiang, and F. Zhang, “Directional couplers realized on silicon-on-insulator,” IEEE Photon. Technol. Lett. 17, 1671–1673 (2005).
[CrossRef]

Chen, J. C.

S. Jungling and J. C. Chen, “A study and optimization of eigenmode calculations using the imaginary-distance beam-propagation method,” IEEE J. Quantum Electron. 30,2098–2105 (1994).
[CrossRef]

Gao, F.

G. B. Cao, F. Gao, J. Jiang, and F. Zhang, “Directional couplers realized on silicon-on-insulator,” IEEE Photon. Technol. Lett. 17, 1671–1673 (2005).
[CrossRef]

Hadley, G. R.

G. R. Hadley and R. E. Smith, “Full-vector waveguide modeling using an iterative finite-difference method with transparent boundary conditions,” J. Lightwave Technol. 13,465–469 (1995).
[CrossRef]

Henry, C. H.

Y. P. Li and C. H. Henry, “Silica-based optical integrated circuits,” IEE Proc.: Optoelectron. 143,263–280 (1996).
[CrossRef]

Hermansson, B.

D. Yevick and B. Hermansson, “New formulations of the matrix beam propagation method: application to rib waveguides,” IEEE J. Quantum Electron. 25,221–229 (1989).
[CrossRef]

Hsu, S. H.

S. H. Hsu, “Polarization-dependent loss compensation on silicon-wire waveguide tap by complex refractive index of metals,” Opt. Lett. 34,1798—1800 (2009).
[CrossRef] [PubMed]

S. H. Hsu, “A 5 μm-thick SOI waveguide with low birefringence and low roughness and optical interconnection using high numerical aperture fiber,” IEEE Photon. Technol. Lett. 20,1003—1005 (2008).
[CrossRef]

Hsu, S.-H.

S.-H. Hsu and Y.-L. Tsai, “Tapping signal power on 12 μm-thick SOI optical waveguide for performance monitoring,” Electron. Lett. 45(3),161–163 (2009).
[CrossRef]

Hua, Heng

C. A. Al Sayeed, A. Vukovic, O. W. W. Yang, and Heng Hua, “Low-loss reconfigurable OADM for metro core optical network,” IET Optoelectron. 1, 178—184 (2007).
[CrossRef]

Jiang, J.

G. B. Cao, F. Gao, J. Jiang, and F. Zhang, “Directional couplers realized on silicon-on-insulator,” IEEE Photon. Technol. Lett. 17, 1671–1673 (2005).
[CrossRef]

Jinguji, K.

K. Jinguji, N. Takato, A. Sugita, and M. Kawachi, “Mach–Zehnder interferometer type optical waveguide coupler with wavelength-flattened coupling ratio,” Electron. Lett. 26, 1326–1327 (1990).
[CrossRef]

Jungling, S.

S. Jungling and J. C. Chen, “A study and optimization of eigenmode calculations using the imaginary-distance beam-propagation method,” IEEE J. Quantum Electron. 30,2098–2105 (1994).
[CrossRef]

Kawachi, M.

K. Jinguji, N. Takato, A. Sugita, and M. Kawachi, “Mach–Zehnder interferometer type optical waveguide coupler with wavelength-flattened coupling ratio,” Electron. Lett. 26, 1326–1327 (1990).
[CrossRef]

Knights, A. P.

G. T. Reed and A. P. Knights, Silicon Photonics—an IntroductionWiley, 2004), Chap. 4.
[CrossRef]

Li, Y. P.

Y. P. Li and C. H. Henry, “Silica-based optical integrated circuits,” IEE Proc.: Optoelectron. 143,263–280 (1996).
[CrossRef]

Little, B. E.

B. E. Little and T. Murphy, “Design rules for maximally flat wavelength-insensitive optical power dividers using Mach–Zehnder structures,” IEEE Photon. Technol. Lett. 9, 1607–1609 (1997).
[CrossRef]

Liu, J.-M.

J.-M. Liu, Photonic Devices (Cambridge Univ. Press, 2005), Chap. 5.
[CrossRef]

Murphy, T.

B. E. Little and T. Murphy, “Design rules for maximally flat wavelength-insensitive optical power dividers using Mach–Zehnder structures,” IEEE Photon. Technol. Lett. 9, 1607–1609 (1997).
[CrossRef]

Petermann, K.

R. A. Soref, J. Schmidtchen, and K. Petermann, “Large single-mode rib waveguides in Ge-Si-Si and Si-on-SiO2,” IEEE J. Quantum Electron. 27,1971–1974 (1991).
[CrossRef]

Pogossian, S.

Powell, O.

Reed, G. T.

G. T. Reed and A. P. Knights, Silicon Photonics—an IntroductionWiley, 2004), Chap. 4.
[CrossRef]

Schmidtchen, J.

R. A. Soref, J. Schmidtchen, and K. Petermann, “Large single-mode rib waveguides in Ge-Si-Si and Si-on-SiO2,” IEEE J. Quantum Electron. 27,1971–1974 (1991).
[CrossRef]

Smith, R. E.

G. R. Hadley and R. E. Smith, “Full-vector waveguide modeling using an iterative finite-difference method with transparent boundary conditions,” J. Lightwave Technol. 13,465–469 (1995).
[CrossRef]

Soref, R. A.

R. A. Soref, J. Schmidtchen, and K. Petermann, “Large single-mode rib waveguides in Ge-Si-Si and Si-on-SiO2,” IEEE J. Quantum Electron. 27,1971–1974 (1991).
[CrossRef]

Sugita, A.

K. Jinguji, N. Takato, A. Sugita, and M. Kawachi, “Mach–Zehnder interferometer type optical waveguide coupler with wavelength-flattened coupling ratio,” Electron. Lett. 26, 1326–1327 (1990).
[CrossRef]

Takato, N.

K. Jinguji, N. Takato, A. Sugita, and M. Kawachi, “Mach–Zehnder interferometer type optical waveguide coupler with wavelength-flattened coupling ratio,” Electron. Lett. 26, 1326–1327 (1990).
[CrossRef]

Tsai, Y.-L.

S.-H. Hsu and Y.-L. Tsai, “Tapping signal power on 12 μm-thick SOI optical waveguide for performance monitoring,” Electron. Lett. 45(3),161–163 (2009).
[CrossRef]

Vescan, L.

Vonsovici, A.

Vukovic, A.

C. A. Al Sayeed, A. Vukovic, O. W. W. Yang, and Heng Hua, “Low-loss reconfigurable OADM for metro core optical network,” IET Optoelectron. 1, 178—184 (2007).
[CrossRef]

Yang, O. W. W.

C. A. Al Sayeed, A. Vukovic, O. W. W. Yang, and Heng Hua, “Low-loss reconfigurable OADM for metro core optical network,” IET Optoelectron. 1, 178—184 (2007).
[CrossRef]

Yariv, A.

A. Yariv and P. Yeh, Photonics: Optical Electronics in Modern Communications, 6th ed. (Oxford Univ. Press, 2007), Chap. 13.

Yeh, P.

A. Yariv and P. Yeh, Photonics: Optical Electronics in Modern Communications, 6th ed. (Oxford Univ. Press, 2007), Chap. 13.

Yevick, D.

D. Yevick and B. Hermansson, “New formulations of the matrix beam propagation method: application to rib waveguides,” IEEE J. Quantum Electron. 25,221–229 (1989).
[CrossRef]

Zhang, F.

G. B. Cao, F. Gao, J. Jiang, and F. Zhang, “Directional couplers realized on silicon-on-insulator,” IEEE Photon. Technol. Lett. 17, 1671–1673 (2005).
[CrossRef]

Electron. Lett.

K. Jinguji, N. Takato, A. Sugita, and M. Kawachi, “Mach–Zehnder interferometer type optical waveguide coupler with wavelength-flattened coupling ratio,” Electron. Lett. 26, 1326–1327 (1990).
[CrossRef]

S.-H. Hsu and Y.-L. Tsai, “Tapping signal power on 12 μm-thick SOI optical waveguide for performance monitoring,” Electron. Lett. 45(3),161–163 (2009).
[CrossRef]

IEE Proc.: Optoelectron.

Y. P. Li and C. H. Henry, “Silica-based optical integrated circuits,” IEE Proc.: Optoelectron. 143,263–280 (1996).
[CrossRef]

IEEE J. Quantum Electron.

D. Yevick and B. Hermansson, “New formulations of the matrix beam propagation method: application to rib waveguides,” IEEE J. Quantum Electron. 25,221–229 (1989).
[CrossRef]

S. Jungling and J. C. Chen, “A study and optimization of eigenmode calculations using the imaginary-distance beam-propagation method,” IEEE J. Quantum Electron. 30,2098–2105 (1994).
[CrossRef]

R. A. Soref, J. Schmidtchen, and K. Petermann, “Large single-mode rib waveguides in Ge-Si-Si and Si-on-SiO2,” IEEE J. Quantum Electron. 27,1971–1974 (1991).
[CrossRef]

IEEE Photon. Technol. Lett.

S. H. Hsu, “A 5 μm-thick SOI waveguide with low birefringence and low roughness and optical interconnection using high numerical aperture fiber,” IEEE Photon. Technol. Lett. 20,1003—1005 (2008).
[CrossRef]

B. E. Little and T. Murphy, “Design rules for maximally flat wavelength-insensitive optical power dividers using Mach–Zehnder structures,” IEEE Photon. Technol. Lett. 9, 1607–1609 (1997).
[CrossRef]

G. B. Cao, F. Gao, J. Jiang, and F. Zhang, “Directional couplers realized on silicon-on-insulator,” IEEE Photon. Technol. Lett. 17, 1671–1673 (2005).
[CrossRef]

IET Optoelectron.

C. A. Al Sayeed, A. Vukovic, O. W. W. Yang, and Heng Hua, “Low-loss reconfigurable OADM for metro core optical network,” IET Optoelectron. 1, 178—184 (2007).
[CrossRef]

J. Lightwave Technol.

Opt. Lett.

Other

G. T. Reed and A. P. Knights, Silicon Photonics—an IntroductionWiley, 2004), Chap. 4.
[CrossRef]

A. Yariv and P. Yeh, Photonics: Optical Electronics in Modern Communications, 6th ed. (Oxford Univ. Press, 2007), Chap. 13.

J.-M. Liu, Photonic Devices (Cambridge Univ. Press, 2005), Chap. 5.
[CrossRef]

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Figures (7)

Fig. 1
Fig. 1

Effective index calculation for (a) symmetrical and (b) antisymmetrical supermodes from two coupled straight waveguides.

Fig. 2
Fig. 2

Coupling length and its detuning versus the waveguide separation in a DC at different polarization states for 5 and 12 μ m thick SOI waveguides.

Fig. 3
Fig. 3

Bending effects from input–output ports in a MZ-based DC for (a) four bending curves, (b) three bending curves, (c) two bending curves.

Fig. 4
Fig. 4

Calculated phenomenological constants of a DC on the SOI waveguide with 12 μ m thickness, 6 μ m width, and 6.8 μ m etch depth.

Fig. 5
Fig. 5

Optical power indication by BPM for conditions under which the waveguide mode exists.

Fig. 6
Fig. 6

MZDC waveguide tap simulated at different etch depths (6.6, 6.8, and 7 μ m ) across the C-band for (a) the tap port power and PDL and (b) primary port power and tap port ratio with and without the bend effect.

Fig. 7
Fig. 7

Transmittance characteristics for the MZDC waveguide tap on (a) tap port power and PDL, (b) primary port power and tap port ratio.

Tables (1)

Tables Icon

Table 1 Coupling Length Study from BPM and Mode Solving for Supermodes

Equations (23)

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

L C = λ 2 ( n S n a ) ,
S = P 2 ( z ) P in = cos 2 θ sin 2 ( ϕ I + ϕ II ) + sin 2 θ sin 2 ( ϕ I ϕ II ) ,
θ = β ( λ ) Δ L 2 ,
ϕ I = π 2 L C d z ,
L C L 0 e d D 0 ,
cos α = 1 ( z L 2 R ) 2 = [ R 2 ( z L 2 ) 2 R 2 ] 1 2 ,
d ( z ) = 2 R ( 1 cos α ) + d 0 = d 0 + 2 R 2 R 2 ( z L 2 ) 2 = d 0 + 2 d ( z ) ,
L C ( d 0 ) L 0 e d 0 D 0 ,
ϕ 6 = L 2 π 2 L C ( z ) d z π 2 L 0 L 2 e [ d 0 + 2 R 2 R 2 ( z L 2 ) 2 ] D 0 d z π 2 L 0 e d 0 D 0 π D 0 R 2 = π 2 L C ( d 0 ) π D 0 R 2 = ϕ 3 ,
ϕ 1 π L 1 2 L 0 e d 0 D 0 = π 2 L C ( d 0 ) L 1 ,
ϕ 2 π L 2 2 L 0 e d 0 D 0 = π 2 L C ( d 0 ) L 2 .
ϕ I = ϕ 1 + ϕ 3 + ϕ 4 π 2 L C ( d 0 ) ( L 1 + π D 0 R ) ,
ϕ II = ϕ 2 + ϕ 5 + ϕ 6 π 2 L C ( d 0 ) ( L 2 + π D 0 R ) .
ϕ 3 = L 1 π 2 L C ( z ) d z π 2 L 0 L 1 e d ( z ) D 0 d z = π 2 L 0 L 1 e [ d 0 + R R 2 ( z L 2 ) 2 ] D 0 d z π 2 L C ( d 0 ) π D 0 R 2 ,
ϕ I = ϕ 1 + ϕ 3 + ϕ 4 π 2 L C ( d 0 ) ( L 1 + π D 0 R 2 + π D 0 R 2 ) ,
ϕ II = ϕ 2 + ϕ 5 + ϕ 6 π 2 L C ( d 0 ) ( L 1 + π D 0 R ) .
ϕ I = ϕ 1 + ϕ 3 + ϕ 4 π 2 L C ( d 0 ) ( L 1 + π D 0 R 2 + π D 0 R 2 ) ,
ϕ II = ϕ 2 + ϕ 5 + ϕ 6 π 2 L C ( d 0 ) ( L 2 + π D 0 R 2 + π D 0 R 2 ) .
ϕ I = a ( 1 + 1 N ) ( 1 + δ ) , ϕ II = a ( 1 1 N ) ( 1 + δ ) ,
cos 2 θ = sin ( 4 a N ) N sin ( 4 a ) + sin ( 4 a N ) .
S = sin ( 4 a N ) sin ( 4 a N ) N sin ( 4 a ) sin 2 ( 2 a ) + N sin ( 4 a ) sin ( 4 a N ) N sin ( 4 a ) sin 2 ( 2 a N ) .
S a = 3 π 8 = 1 4 sin ( 3 π N ) N + sin ( 3 π 2 N ) + sin 2 ( 3 π 4 N ) .
ln ( 1 L C ) ln ( 1 L 0 ) d D 0 .

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