Abstract

A cross-slot waveguide geometry provides high confinement of the mode field of both fundamental quasi-TE and quasi-TM modes in geometrically perpendicular slots. A unique possibility to tailor optical mode characteristics such as effective index and confinement factor quite independently for the two polarizations with geometric and material parameters is shown. Nonbirefringent cross-slot geometries are presented. Fabrication related tolerances of the cross-slot geometry for low birefringence operation are studied. Means to externally tune the birefringence by a thermo-optic effect is also analyzed. Fabrication of a cross-slot waveguide test structure is demonstrated.

© 2009 Optical Society of America

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References

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    [CrossRef] [PubMed]
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    [CrossRef]
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    [CrossRef] [PubMed]
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  8. J. V. Galan, P. Sanchis, J. Garcia, J. Blasco, A. Martinez, and J. Martí, “Study of asymmetric silicon cross-slot waveguides for polarization diversity schemes,” Appl. Opt. 48, 2693-2696(2009).
    [CrossRef] [PubMed]
  9. T. Alasaarela, A. Säynätjoki, P. Stenberg, M. Kuittinen, and S. Honkanen, “Filling of slot waveguides with versatile material systems using atomic layer deposition,” presented at Integrated Photonics and Nanophotonics Research and Applications (IPNRA), Honolulu, Hawaii, USA, 12-17 July 2009, paper JTuB4.
  10. Fimmwave, Photon Design, Version 5.1.
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    [CrossRef]
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    [CrossRef]
  13. M. Iodice, G. Mazzi, and L. Sirleto, “Thermo-optical static and dynamic analysis of a digital optical switch based on amorphous silicon waveguide,” Opt. Express 14, 5266-5278 (2006).
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2009 (2)

C. Koos, P. Vorreau, T. Vallaitis, P. Dumon, W. Bogaerts, R. Baets, B. Esembeson, I. Biaggio, T. Michinobu, F. Diederich, W. Freude, and J. Leuthold, “All-optical high-speed signal processing with silicon-organic hybrid slot waveguides,” Nat. Photon. 3, 216-219 (2009).
[CrossRef]

J. V. Galan, P. Sanchis, J. Garcia, J. Blasco, A. Martinez, and J. Martí, “Study of asymmetric silicon cross-slot waveguides for polarization diversity schemes,” Appl. Opt. 48, 2693-2696(2009).
[CrossRef] [PubMed]

2007 (1)

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

2006 (1)

2005 (2)

2004 (3)

2003 (1)

1993 (1)

A. Sv. Sudbo, “Film mode matching: a versatile numerical method for vector mode field calculation in dielectric waveguides,” Pure Appl. Opt. 2, 211-233 (1993).
[CrossRef]

Alasaarela, T.

T. Alasaarela, A. Säynätjoki, P. Stenberg, M. Kuittinen, and S. Honkanen, “Filling of slot waveguides with versatile material systems using atomic layer deposition,” presented at Integrated Photonics and Nanophotonics Research and Applications (IPNRA), Honolulu, Hawaii, USA, 12-17 July 2009, paper JTuB4.

A. Säynätjoki, T. Alasaarela, A. Khanna, L. Karvonen, A. Tervonen, and S. Honkanen, “Advantages of angled sidewalls in slot waveguides,” presented at Integrated Photonics and Nanophotonics Research and Applications (IPNRA), Honolulu, Hawaii, USA, 12-17 July 2009, paper ITuE2.

Almeida, V. R.

Andreani, L. C.

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

Baets, R.

C. Koos, P. Vorreau, T. Vallaitis, P. Dumon, W. Bogaerts, R. Baets, B. Esembeson, I. Biaggio, T. Michinobu, F. Diederich, W. Freude, and J. Leuthold, “All-optical high-speed signal processing with silicon-organic hybrid slot waveguides,” Nat. Photon. 3, 216-219 (2009).
[CrossRef]

Barrios, C. A.

Biaggio, I.

C. Koos, P. Vorreau, T. Vallaitis, P. Dumon, W. Bogaerts, R. Baets, B. Esembeson, I. Biaggio, T. Michinobu, F. Diederich, W. Freude, and J. Leuthold, “All-optical high-speed signal processing with silicon-organic hybrid slot waveguides,” Nat. Photon. 3, 216-219 (2009).
[CrossRef]

Bienstman, P.

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

Blasco, J.

Bogaerts, W.

C. Koos, P. Vorreau, T. Vallaitis, P. Dumon, W. Bogaerts, R. Baets, B. Esembeson, I. Biaggio, T. Michinobu, F. Diederich, W. Freude, and J. Leuthold, “All-optical high-speed signal processing with silicon-organic hybrid slot waveguides,” Nat. Photon. 3, 216-219 (2009).
[CrossRef]

Costa, R.

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

Dems, M.

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

Diederich, F.

C. Koos, P. Vorreau, T. Vallaitis, P. Dumon, W. Bogaerts, R. Baets, B. Esembeson, I. Biaggio, T. Michinobu, F. Diederich, W. Freude, and J. Leuthold, “All-optical high-speed signal processing with silicon-organic hybrid slot waveguides,” Nat. Photon. 3, 216-219 (2009).
[CrossRef]

Dumon, P.

C. Koos, P. Vorreau, T. Vallaitis, P. Dumon, W. Bogaerts, R. Baets, B. Esembeson, I. Biaggio, T. Michinobu, F. Diederich, W. Freude, and J. Leuthold, “All-optical high-speed signal processing with silicon-organic hybrid slot waveguides,” Nat. Photon. 3, 216-219 (2009).
[CrossRef]

Esembeson, B.

C. Koos, P. Vorreau, T. Vallaitis, P. Dumon, W. Bogaerts, R. Baets, B. Esembeson, I. Biaggio, T. Michinobu, F. Diederich, W. Freude, and J. Leuthold, “All-optical high-speed signal processing with silicon-organic hybrid slot waveguides,” Nat. Photon. 3, 216-219 (2009).
[CrossRef]

Freude, W.

C. Koos, P. Vorreau, T. Vallaitis, P. Dumon, W. Bogaerts, R. Baets, B. Esembeson, I. Biaggio, T. Michinobu, F. Diederich, W. Freude, and J. Leuthold, “All-optical high-speed signal processing with silicon-organic hybrid slot waveguides,” Nat. Photon. 3, 216-219 (2009).
[CrossRef]

Galan, J. V.

Garcia, J.

Haus, H. A.

Honkanen, S.

A. Khanna, A. Säynätjoki, A. Tervonen, and S. Honkanen, “Non-birefringent cross-slot waveguide,” presented at CLEO Europe 2009, Munich, Germany, 14-19 June 2009, paper CK.P.10.

T. Alasaarela, A. Säynätjoki, P. Stenberg, M. Kuittinen, and S. Honkanen, “Filling of slot waveguides with versatile material systems using atomic layer deposition,” presented at Integrated Photonics and Nanophotonics Research and Applications (IPNRA), Honolulu, Hawaii, USA, 12-17 July 2009, paper JTuB4.

A. Säynätjoki, T. Alasaarela, A. Khanna, L. Karvonen, A. Tervonen, and S. Honkanen, “Advantages of angled sidewalls in slot waveguides,” presented at Integrated Photonics and Nanophotonics Research and Applications (IPNRA), Honolulu, Hawaii, USA, 12-17 July 2009, paper ITuE2.

Hopman, W. C. L.

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

Hugonin, J. P.

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

Iodice, M.

Ippen, E. P.

Karvonen, L.

A. Säynätjoki, T. Alasaarela, A. Khanna, L. Karvonen, A. Tervonen, and S. Honkanen, “Advantages of angled sidewalls in slot waveguides,” presented at Integrated Photonics and Nanophotonics Research and Applications (IPNRA), Honolulu, Hawaii, USA, 12-17 July 2009, paper ITuE2.

Khanna, A.

A. Khanna, A. Säynätjoki, A. Tervonen, and S. Honkanen, “Non-birefringent cross-slot waveguide,” presented at CLEO Europe 2009, Munich, Germany, 14-19 June 2009, paper CK.P.10.

A. Säynätjoki, T. Alasaarela, A. Khanna, L. Karvonen, A. Tervonen, and S. Honkanen, “Advantages of angled sidewalls in slot waveguides,” presented at Integrated Photonics and Nanophotonics Research and Applications (IPNRA), Honolulu, Hawaii, USA, 12-17 July 2009, paper ITuE2.

Koos, C.

C. Koos, P. Vorreau, T. Vallaitis, P. Dumon, W. Bogaerts, R. Baets, B. Esembeson, I. Biaggio, T. Michinobu, F. Diederich, W. Freude, and J. Leuthold, “All-optical high-speed signal processing with silicon-organic hybrid slot waveguides,” Nat. Photon. 3, 216-219 (2009).
[CrossRef]

Kuittinen, M.

T. Alasaarela, A. Säynätjoki, P. Stenberg, M. Kuittinen, and S. Honkanen, “Filling of slot waveguides with versatile material systems using atomic layer deposition,” presented at Integrated Photonics and Nanophotonics Research and Applications (IPNRA), Honolulu, Hawaii, USA, 12-17 July 2009, paper JTuB4.

Lalanne, P.

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

Leuthold, J.

C. Koos, P. Vorreau, T. Vallaitis, P. Dumon, W. Bogaerts, R. Baets, B. Esembeson, I. Biaggio, T. Michinobu, F. Diederich, W. Freude, and J. Leuthold, “All-optical high-speed signal processing with silicon-organic hybrid slot waveguides,” Nat. Photon. 3, 216-219 (2009).
[CrossRef]

Li, C.

Lipson, M.

Martí, J.

Martinez, A.

Mazzi, G.

Melloni, A.

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

Michinobu, T.

C. Koos, P. Vorreau, T. Vallaitis, P. Dumon, W. Bogaerts, R. Baets, B. Esembeson, I. Biaggio, T. Michinobu, F. Diederich, W. Freude, and J. Leuthold, “All-optical high-speed signal processing with silicon-organic hybrid slot waveguides,” Nat. Photon. 3, 216-219 (2009).
[CrossRef]

Obayya, S. S. A.

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

Panajotov, K.

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

Panepucci, R. R.

Pinto, D.

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

Rosa, L.

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

Sanchis, P.

Säynätjoki, A.

A. Khanna, A. Säynätjoki, A. Tervonen, and S. Honkanen, “Non-birefringent cross-slot waveguide,” presented at CLEO Europe 2009, Munich, Germany, 14-19 June 2009, paper CK.P.10.

T. Alasaarela, A. Säynätjoki, P. Stenberg, M. Kuittinen, and S. Honkanen, “Filling of slot waveguides with versatile material systems using atomic layer deposition,” presented at Integrated Photonics and Nanophotonics Research and Applications (IPNRA), Honolulu, Hawaii, USA, 12-17 July 2009, paper JTuB4.

A. Säynätjoki, T. Alasaarela, A. Khanna, L. Karvonen, A. Tervonen, and S. Honkanen, “Advantages of angled sidewalls in slot waveguides,” presented at Integrated Photonics and Nanophotonics Research and Applications (IPNRA), Honolulu, Hawaii, USA, 12-17 July 2009, paper ITuE2.

Selleri, S.

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

Sirleto, L.

Stenberg, P.

T. Alasaarela, A. Säynätjoki, P. Stenberg, M. Kuittinen, and S. Honkanen, “Filling of slot waveguides with versatile material systems using atomic layer deposition,” presented at Integrated Photonics and Nanophotonics Research and Applications (IPNRA), Honolulu, Hawaii, USA, 12-17 July 2009, paper JTuB4.

Sudbo, A. Sv.

A. Sv. Sudbo, “Film mode matching: a versatile numerical method for vector mode field calculation in dielectric waveguides,” Pure Appl. Opt. 2, 211-233 (1993).
[CrossRef]

Tervonen, A.

A. Khanna, A. Säynätjoki, A. Tervonen, and S. Honkanen, “Non-birefringent cross-slot waveguide,” presented at CLEO Europe 2009, Munich, Germany, 14-19 June 2009, paper CK.P.10.

A. Säynätjoki, T. Alasaarela, A. Khanna, L. Karvonen, A. Tervonen, and S. Honkanen, “Advantages of angled sidewalls in slot waveguides,” presented at Integrated Photonics and Nanophotonics Research and Applications (IPNRA), Honolulu, Hawaii, USA, 12-17 July 2009, paper ITuE2.

Uranus, H. P.

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

Vallaitis, T.

C. Koos, P. Vorreau, T. Vallaitis, P. Dumon, W. Bogaerts, R. Baets, B. Esembeson, I. Biaggio, T. Michinobu, F. Diederich, W. Freude, and J. Leuthold, “All-optical high-speed signal processing with silicon-organic hybrid slot waveguides,” Nat. Photon. 3, 216-219 (2009).
[CrossRef]

Vorreau, P.

C. Koos, P. Vorreau, T. Vallaitis, P. Dumon, W. Bogaerts, R. Baets, B. Esembeson, I. Biaggio, T. Michinobu, F. Diederich, W. Freude, and J. Leuthold, “All-optical high-speed signal processing with silicon-organic hybrid slot waveguides,” Nat. Photon. 3, 216-219 (2009).
[CrossRef]

Watts, M. R.

Xu, Q.

Xu, Y. Z.

Zhao, X.

Appl. Opt. (1)

Nat. Photon. (1)

C. Koos, P. Vorreau, T. Vallaitis, P. Dumon, W. Bogaerts, R. Baets, B. Esembeson, I. Biaggio, T. Michinobu, F. Diederich, W. Freude, and J. Leuthold, “All-optical high-speed signal processing with silicon-organic hybrid slot waveguides,” Nat. Photon. 3, 216-219 (2009).
[CrossRef]

Opt. Express (1)

Opt. Lett. (6)

Opt. Quantum Electron. (1)

P. Bienstman, S. Selleri, L. Rosa, H. P. Uranus, W. C. L. Hopman, R. Costa, A. Melloni, L. C. Andreani, J. P. Hugonin, P. Lalanne, D. Pinto, S. S. A. Obayya, M. Dems, and K. Panajotov, “Modelling leaky photonic wires: a mode solver comparison,” Opt. Quantum Electron. 38, 731-759 (2007).
[CrossRef]

Pure Appl. Opt. (1)

A. Sv. Sudbo, “Film mode matching: a versatile numerical method for vector mode field calculation in dielectric waveguides,” Pure Appl. Opt. 2, 211-233 (1993).
[CrossRef]

Other (4)

A. Säynätjoki, T. Alasaarela, A. Khanna, L. Karvonen, A. Tervonen, and S. Honkanen, “Advantages of angled sidewalls in slot waveguides,” presented at Integrated Photonics and Nanophotonics Research and Applications (IPNRA), Honolulu, Hawaii, USA, 12-17 July 2009, paper ITuE2.

T. Alasaarela, A. Säynätjoki, P. Stenberg, M. Kuittinen, and S. Honkanen, “Filling of slot waveguides with versatile material systems using atomic layer deposition,” presented at Integrated Photonics and Nanophotonics Research and Applications (IPNRA), Honolulu, Hawaii, USA, 12-17 July 2009, paper JTuB4.

Fimmwave, Photon Design, Version 5.1.

A. Khanna, A. Säynätjoki, A. Tervonen, and S. Honkanen, “Non-birefringent cross-slot waveguide,” presented at CLEO Europe 2009, Munich, Germany, 14-19 June 2009, paper CK.P.10.

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Figures (9)

Fig. 1
Fig. 1

Schematic of a cross-slot waveguide. Rail width w r , rail height h, vertical slot width w s , horizontal slot height h s , depth of the horizontal slot d, thickness of the cover material c, and refractive indices of different material layers are shown. When n h = n v , the configuration is called uniform, whereas when n h n v , it is termed nonuniform. Refractive index of the substrate n is 1.46 ( Si O 2 ) and the rails n r is 3.58 (Si) for all simulations.

Fig. 2
Fig. 2

Single mode regime is shown with variations in rail width w r and rail height h for uniform cross-slot structure, where w s = h s = 60 nm , c = 100 nm , d = ( h h s ) / 2 , and n h = n v = 1.46 . Top, two maxima can be observed in quasi-TE and quasi-TM mode intensity distributions on either side of the crossing.

Fig. 3
Fig. 3

Equal effective indices for quasi-TE and quasi-TM modes, shown by arrow, are observed for both uniform ( n h = n v = 1.46 ) and nonuniform ( n h = 1.46 and n v = 1.63 ) configurations when vertical slot width w s = 120 nm and depth d is centered ( d = ( h h s ) / 2 ). For uniform structure w r = 200 nm and h = 400 nm , and for nonuniform structure w r = 160 nm and h = 380 nm .

Fig. 4
Fig. 4

Variation of effective-index and confinement factor of fundamental (a) quasi-TM and (b) quasi-TE modes with horizontal slot depth d. Minimum effective index corresponds to highest confinement within the slot region for quasi-TM mode. Quasi-TE mode is relatively unaffected with changes in horizontal slot depth d. Intensity distributions for depth d = 30 nm are shown, indicated by position (i), and for d = 150 nm , indicated by position (ii). Parameters used for simulation are w r = 160 nm , h = 380 nm , w s = h s = 60 nm , c = 100 nm , and n h = n v = 1.46 .

Fig. 5
Fig. 5

Variation of effective index is shown with temperature for the fundamental quasi-TE and quasi-TM modes. Common parameters in simulations are h = 380 nm , w s = 60 nm , c = 100 nm , n h = 1.46 at 298 K , n h / T = n v / T = 10 5 K 1 and n r / T = 2 × 10 4 K 1 . (a)  w r = 200 nm , h s = 56 nm , d = 70 nm , and n v = 1.63 . (b)  w r = 160 nm , h s = 67 nm , d = ( h h s ) / 2 , and n v = 1.46 .

Fig. 6
Fig. 6

Schematic of an angled sidewall cross-slot waveguide section with vertical slot base width w b . In angled sidewall geometry, vertical slot width w s and rail width w r are defined at depth of h / 2 .

Fig. 7
Fig. 7

Variation of birefringence with horizontal slot depth d, in an angled sidewall cross-slot waveguide. Zero birefringence is shown with an arrow. Other geometrical parameters are w r = 160 nm , h = 380 nm , w s = 100 nm , h s = 60 nm , w b = 60 nm , c = 100 nm , and n h = n v = 1.46 . Top, mode intensity distributions of the quasi-TE and quasi-TM modes.

Fig. 8
Fig. 8

(a) Confinement factor of the quasi-TE and quasi-TM modes with variation of horizontal slot depth d, in cross-slot waveguide with angled sidewall. Parameters used for simulation are w r = 160 nm , h = 450 nm , w s = 100 nm , w b = 60 nm , h s = 80 nm , c = 100 nm , and n h = n v = 1.46 . (b) Variation of effective index of quasi-TE and quasi-TM modes with temperature. Fine-tuning of birefringence externally by thermo-optic means to realize zero birefringence is shown (arrow). Parameters used in simulation are w r = 160 nm , h = 380 nm , w s = 100 nm , w b = 60 nm , h s = 100 nm , d = 41 nm , c = 100 nm , n h = 1.46 , n v = 1.63 , n h / T = n v / T = 10 5 K 1 , and n r / T = 2 × 10 4 K 1 at 298 K .

Fig. 9
Fig. 9

Test structures of cross-slot waveguide with no cover material. Sandwich layers of a-Si:H/SiOx/a-Si:H are deposited by PECVD over thermally oxidized silicon. FIB milling is used to obtain the vertical sections.

Tables (1)

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Table 1 Slope Depicting Change in Birefringence with Change in Geometric Parameters a

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