Abstract

We present a direct strip-slot waveguide mode coupler without any auxiliary structures. Contrary to popular belief, an apparent mode mismatch between strip and slot waveguide does not deteriorate conversion efficiency. Separated electric and magnetic field distributions in a slot waveguide lead to highly efficient modal coupling in the direct strip-slot coupler and result in high conversion efficiency. Accurate experimental characterization shows that the direct strip-slot waveguide mode coupler is capable of up to 96% conversion efficiency with a broad bandwidth. Being simplest and of high efficiency, the direct strip-slot waveguide mode coupler can encourage potential applications of slot waveguides.

© 2016 Optical Society of America

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References

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    [Crossref]
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2016 (1)

2015 (1)

P. Steglich, C. Mai, D. Stolarek, S. Lischke, S. Kupijai, C. Villringer, S. Pulwer, F. Heinrich, J. Bauer, S. Meister, D. Knoll, M. Casalboni, and S. Schrader, “Novel ring resonator combining strong field confinement with high optical quality factor,” IEEE Photonics Technol. Lett. 27(20), 2197–2200 (2015).
[Crossref]

2014 (2)

2011 (1)

2009 (3)

Z. Wang, N. Zhu, Y. Tang, L. Wosinski, D. Dai, and S. He, “Ultracompact low-loss coupler between strip and slot waveguides,” Opt. Lett. 34(10), 1498–1500 (2009).
[Crossref] [PubMed]

T. Claes, J. G. Molera, K. De Vos, E. Schacht, R. Baets, and P. Bienstman, “Label-free biosensing with a slot-waveguide-based ring resonator in silicon on insulator,” IEEE Photonics J. 1(3), 197–204 (2009).
[Crossref]

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. Photonics 3(4), 216–219 (2009).
[Crossref]

2008 (1)

2007 (3)

2005 (2)

T. Baehr-Jones, M. Hochberg, C. Walker, and A. Scherer, “High-Q optical resonators in silicon-on-insulator-based slot waveguides,” Appl. Phys. Lett. 86(8), 081101 (2005).
[Crossref]

M. Borselli, T. Johnson, and O. Painter, “Beyond the Rayleigh scattering limit in high-Q silicon microdisks: theory and experiment,” Opt. Express 13(5), 1515–1530 (2005).
[Crossref] [PubMed]

2004 (3)

Alasaarela, T.

Almeida, V. R.

Baehr-Jones, T.

T. Baehr-Jones, M. Hochberg, C. Walker, and A. Scherer, “High-Q optical resonators in silicon-on-insulator-based slot waveguides,” Appl. Phys. Lett. 86(8), 081101 (2005).
[Crossref]

Baets, R.

T. Claes, J. G. Molera, K. De Vos, E. Schacht, R. Baets, and P. Bienstman, “Label-free biosensing with a slot-waveguide-based ring resonator in silicon on insulator,” IEEE Photonics J. 1(3), 197–204 (2009).
[Crossref]

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. Photonics 3(4), 216–219 (2009).
[Crossref]

Barrios, C. A.

Bauer, J.

P. Steglich, C. Mai, D. Stolarek, S. Lischke, S. Kupijai, C. Villringer, S. Pulwer, F. Heinrich, J. Bauer, S. Meister, D. Knoll, M. Casalboni, and S. Schrader, “Novel ring resonator combining strong field confinement with high optical quality factor,” IEEE Photonics Technol. Lett. 27(20), 2197–2200 (2015).
[Crossref]

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. Photonics 3(4), 216–219 (2009).
[Crossref]

Bienstman, P.

T. Claes, J. G. Molera, K. De Vos, E. Schacht, R. Baets, and P. Bienstman, “Label-free biosensing with a slot-waveguide-based ring resonator in silicon on insulator,” IEEE Photonics J. 1(3), 197–204 (2009).
[Crossref]

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. Photonics 3(4), 216–219 (2009).
[Crossref]

Bolivar, P. H.

Borselli, M.

Casalboni, M.

P. Steglich, C. Mai, D. Stolarek, S. Lischke, S. Kupijai, C. Villringer, S. Pulwer, F. Heinrich, J. Bauer, S. Meister, D. Knoll, M. Casalboni, and S. Schrader, “Novel ring resonator combining strong field confinement with high optical quality factor,” IEEE Photonics Technol. Lett. 27(20), 2197–2200 (2015).
[Crossref]

Casquel, R.

Claes, T.

T. Claes, J. G. Molera, K. De Vos, E. Schacht, R. Baets, and P. Bienstman, “Label-free biosensing with a slot-waveguide-based ring resonator in silicon on insulator,” IEEE Photonics J. 1(3), 197–204 (2009).
[Crossref]

Dai, D.

De Vos, K.

T. Claes, J. G. Molera, K. De Vos, E. Schacht, R. Baets, and P. Bienstman, “Label-free biosensing with a slot-waveguide-based ring resonator in silicon on insulator,” IEEE Photonics J. 1(3), 197–204 (2009).
[Crossref]

Deng, Q.

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. Photonics 3(4), 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. Photonics 3(4), 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. Photonics 3(4), 216–219 (2009).
[Crossref]

Feng, N. N.

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. Photonics 3(4), 216–219 (2009).
[Crossref]

Griol, A.

Gylfason, K. B.

He, S.

Heinrich, F.

P. Steglich, C. Mai, D. Stolarek, S. Lischke, S. Kupijai, C. Villringer, S. Pulwer, F. Heinrich, J. Bauer, S. Meister, D. Knoll, M. Casalboni, and S. Schrader, “Novel ring resonator combining strong field confinement with high optical quality factor,” IEEE Photonics Technol. Lett. 27(20), 2197–2200 (2015).
[Crossref]

Henschel, W.

Hiltunen, M.

Hochberg, M.

T. Baehr-Jones, M. Hochberg, C. Walker, and A. Scherer, “High-Q optical resonators in silicon-on-insulator-based slot waveguides,” Appl. Phys. Lett. 86(8), 081101 (2005).
[Crossref]

Holgado, M.

Honkanen, S.

Huang, W.-P.

Johnson, T.

Karvonen, L.

Khan, M. H.

Kim, S.

Kimerling, L. C.

Knoll, D.

P. Steglich, C. Mai, D. Stolarek, S. Lischke, S. Kupijai, C. Villringer, S. Pulwer, F. Heinrich, J. Bauer, S. Meister, D. Knoll, M. Casalboni, and S. Schrader, “Novel ring resonator combining strong field confinement with high optical quality factor,” IEEE Photonics Technol. Lett. 27(20), 2197–2200 (2015).
[Crossref]

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. Photonics 3(4), 216–219 (2009).
[Crossref]

Kupijai, S.

P. Steglich, C. Mai, D. Stolarek, S. Lischke, S. Kupijai, C. Villringer, S. Pulwer, F. Heinrich, J. Bauer, S. Meister, D. Knoll, M. Casalboni, and S. Schrader, “Novel ring resonator combining strong field confinement with high optical quality factor,” IEEE Photonics Technol. Lett. 27(20), 2197–2200 (2015).
[Crossref]

Kurz, H.

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. Photonics 3(4), 216–219 (2009).
[Crossref]

Li, X.

Liow, T. Y.

Lipson, M.

Lischke, S.

P. Steglich, C. Mai, D. Stolarek, S. Lischke, S. Kupijai, C. Villringer, S. Pulwer, F. Heinrich, J. Bauer, S. Meister, D. Knoll, M. Casalboni, and S. Schrader, “Novel ring resonator combining strong field confinement with high optical quality factor,” IEEE Photonics Technol. Lett. 27(20), 2197–2200 (2015).
[Crossref]

Liu, L.

Lo, G. Q.

Mai, C.

P. Steglich, C. Mai, D. Stolarek, S. Lischke, S. Kupijai, C. Villringer, S. Pulwer, F. Heinrich, J. Bauer, S. Meister, D. Knoll, M. Casalboni, and S. Schrader, “Novel ring resonator combining strong field confinement with high optical quality factor,” IEEE Photonics Technol. Lett. 27(20), 2197–2200 (2015).
[Crossref]

McNab, S.

Meister, S.

P. Steglich, C. Mai, D. Stolarek, S. Lischke, S. Kupijai, C. Villringer, S. Pulwer, F. Heinrich, J. Bauer, S. Meister, D. Knoll, M. Casalboni, and S. Schrader, “Novel ring resonator combining strong field confinement with high optical quality factor,” IEEE Photonics Technol. Lett. 27(20), 2197–2200 (2015).
[Crossref]

Michel, J.

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. Photonics 3(4), 216–219 (2009).
[Crossref]

Molera, J. G.

T. Claes, J. G. Molera, K. De Vos, E. Schacht, R. Baets, and P. Bienstman, “Label-free biosensing with a slot-waveguide-based ring resonator in silicon on insulator,” IEEE Photonics J. 1(3), 197–204 (2009).
[Crossref]

Mu, J.

Niehusmann, J.

Painter, O.

Pulwer, S.

P. Steglich, C. Mai, D. Stolarek, S. Lischke, S. Kupijai, C. Villringer, S. Pulwer, F. Heinrich, J. Bauer, S. Meister, D. Knoll, M. Casalboni, and S. Schrader, “Novel ring resonator combining strong field confinement with high optical quality factor,” IEEE Photonics Technol. Lett. 27(20), 2197–2200 (2015).
[Crossref]

Qi, M.

Sánchez, B.

Säynätjoki, A.

Schacht, E.

T. Claes, J. G. Molera, K. De Vos, E. Schacht, R. Baets, and P. Bienstman, “Label-free biosensing with a slot-waveguide-based ring resonator in silicon on insulator,” IEEE Photonics J. 1(3), 197–204 (2009).
[Crossref]

Scherer, A.

T. Baehr-Jones, M. Hochberg, C. Walker, and A. Scherer, “High-Q optical resonators in silicon-on-insulator-based slot waveguides,” Appl. Phys. Lett. 86(8), 081101 (2005).
[Crossref]

Schrader, S.

P. Steglich, C. Mai, D. Stolarek, S. Lischke, S. Kupijai, C. Villringer, S. Pulwer, F. Heinrich, J. Bauer, S. Meister, D. Knoll, M. Casalboni, and S. Schrader, “Novel ring resonator combining strong field confinement with high optical quality factor,” IEEE Photonics Technol. Lett. 27(20), 2197–2200 (2015).
[Crossref]

Shen, H.

Sohlström, H.

Steglich, P.

P. Steglich, C. Mai, D. Stolarek, S. Lischke, S. Kupijai, C. Villringer, S. Pulwer, F. Heinrich, J. Bauer, S. Meister, D. Knoll, M. Casalboni, and S. Schrader, “Novel ring resonator combining strong field confinement with high optical quality factor,” IEEE Photonics Technol. Lett. 27(20), 2197–2200 (2015).
[Crossref]

Stolarek, D.

P. Steglich, C. Mai, D. Stolarek, S. Lischke, S. Kupijai, C. Villringer, S. Pulwer, F. Heinrich, J. Bauer, S. Meister, D. Knoll, M. Casalboni, and S. Schrader, “Novel ring resonator combining strong field confinement with high optical quality factor,” IEEE Photonics Technol. Lett. 27(20), 2197–2200 (2015).
[Crossref]

Sun, R.

Tang, Y.

Tervonen, A.

Thylén, L.

L. Thylén and L. Wosinski, “Integrated photonics in the 21st century,” Photonics Res. 2(2), 75–81 (2014).
[Crossref]

Tu, X.

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. Photonics 3(4), 216–219 (2009).
[Crossref]

Villringer, C.

P. Steglich, C. Mai, D. Stolarek, S. Lischke, S. Kupijai, C. Villringer, S. Pulwer, F. Heinrich, J. Bauer, S. Meister, D. Knoll, M. Casalboni, and S. Schrader, “Novel ring resonator combining strong field confinement with high optical quality factor,” IEEE Photonics Technol. Lett. 27(20), 2197–2200 (2015).
[Crossref]

Vlasov, Y.

Vörckel, A.

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. Photonics 3(4), 216–219 (2009).
[Crossref]

Wahlbrink, T.

Walker, C.

T. Baehr-Jones, M. Hochberg, C. Walker, and A. Scherer, “High-Q optical resonators in silicon-on-insulator-based slot waveguides,” Appl. Phys. Lett. 86(8), 081101 (2005).
[Crossref]

Wang, Z.

Wosinski, L.

Xiao, S.

Xu, Q.

Zhou, Z.

Zhu, N.

Appl. Phys. Lett. (1)

T. Baehr-Jones, M. Hochberg, C. Walker, and A. Scherer, “High-Q optical resonators in silicon-on-insulator-based slot waveguides,” Appl. Phys. Lett. 86(8), 081101 (2005).
[Crossref]

IEEE Photonics J. (1)

T. Claes, J. G. Molera, K. De Vos, E. Schacht, R. Baets, and P. Bienstman, “Label-free biosensing with a slot-waveguide-based ring resonator in silicon on insulator,” IEEE Photonics J. 1(3), 197–204 (2009).
[Crossref]

IEEE Photonics Technol. Lett. (1)

P. Steglich, C. Mai, D. Stolarek, S. Lischke, S. Kupijai, C. Villringer, S. Pulwer, F. Heinrich, J. Bauer, S. Meister, D. Knoll, M. Casalboni, and S. Schrader, “Novel ring resonator combining strong field confinement with high optical quality factor,” IEEE Photonics Technol. Lett. 27(20), 2197–2200 (2015).
[Crossref]

Nat. Photonics (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. Photonics 3(4), 216–219 (2009).
[Crossref]

Opt. Express (6)

Opt. Lett. (6)

Photonics Res. (1)

L. Thylén and L. Wosinski, “Integrated photonics in the 21st century,” Photonics Res. 2(2), 75–81 (2014).
[Crossref]

Other (3)

M. Teng, B. Niu, K. Han, and M. Qi, “Effect of waveguide surface roughness on the fiber coupling efficiency of inverse tapers,” in Optical Fiber Communication Conference, OSA Technical Digest (online) (Optical Society of America, 2015), paper Th3F.6.
[Crossref]

E. Neumann, “7. Launching of modes,” in Single-Mode Fibers: Fundamentals, (Springer-Verlag, 1988), pp. 167–193.

H. Kogelnik, “Theory of dielectric waveguides,” in Integrated Optics, T. Tamir ed. (Springer, 1975), pp. 13–81.

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Figures (6)

Fig. 1
Fig. 1 (a) Schematic of the direct strip-slot mode coupler. The silicon waveguide (blue) is cladded with SiO2 (light blue). (b) Comparison of electric field and magnetic field distributions for the fundamental TE modes on the strip (A-A’) and slot waveguide cross-sections (B-B’).
Fig. 2
Fig. 2 Calculated mode overlaps using Eq. (1) (dashed) and Eq. (2) (solid) for the coupler configuration shown in Fig. 1(a) with various slot gap sizes (Wgap). Wslot is 300 nm and the operating wavelength is 1550 nm. Crosses are the measured conversion efficiencies.
Fig. 3
Fig. 3 Simulated (a) mode propagation from the left input strip waveguide mode to the right output slot waveguide mode. (b) Conversion efficiencies of direct couplers with various upper cladding indices. The lower cladding is always SiO2, and Wgap = 60 nm.
Fig. 4
Fig. 4 (a) Scanning electron microscope (SEM) micrograph of the racetrack resonator before upper cladding deposition. The racetrack has a pair of direct couplers on one straight arm. (b) Tilted SEM micrograph of the fabricated direct strip-slot mode coupler. (c) Transmission spectra for the racetrack with the direct coupler (red) and the reference resonator without the direct coupler (blue).
Fig. 5
Fig. 5 Measured (solid blue) and fitted (circled red) transmission near a resonant dip of the racetrack resonator: (a) the reference resonator and (b) the resonator with the direct coupler. (c) Characterized conversion efficiencies at various resonance dips
Fig. 6
Fig. 6 Measured transmission (blue lines) and characterized conversion efficiency (red) spectra of the direct strip-slot coupler

Tables (1)

Tables Icon

Table 1 Comparison of the conversion efficiencies and the device lengths

Equations (3)

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

η 1 = | E 1 E 2 * ds | 2 | E 1 | 2 ds | E 2 | 2 ds
η 2 =( Re{ E 1 × H 2 * ds } E 1 × H 1 * ds )( Re{ E 2 × H 1 * ds } E 2 × H 2 * ds )
Q i = 2 Q t 1+ T min

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