Abstract

Novel class of microstructured optical fiber couplers is introduced that operates by resonant, rather than proximity, energy transfer via transverse lightguides built into a fiber cross-section. Such a design allows unlimited spatial separation between interacting fibers which, in turn, eliminates inter-core crosstalk via proximity coupling. Controllable energy transfer between fiber cores is then achieved by localized and highly directional transmission through a transverse lightguide. Main advantage of this coupling scheme is its inherent scalability as additional fiber cores could be integrated into the existing fiber cross-section simply by placing them far enough from the existing circuitry to avoid proximity crosstalk, and then making the necessary inter-core connections with transverse light “wires” - in a direct analogy with an on chip electronics integration.

© 2005 Optical Society of America

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  1. C.M. Smith, N. Venkataraman, M.T. Gallagher, D. Muller, J.A. West, N.F. Borrelli, D.C. Allan, K.W. Koch, “Low-loss hollow-core silica/air photonic bandgap fibre,” Nature 424, 657–659 (2003).
    [CrossRef] [PubMed]
  2. P. Russell, ”Photonic crystal fibers,” Science 299, 358–362 (2003).
    [CrossRef] [PubMed]
  3. M.A. van Eijkelenborg, A. Argyros, G. Barton, I.M. Bassett, M. Fellew, G. Henry, N.A. Issa, M.C.J. Large, S. Manos, W. Padden, L. Poladian, J. Zagari, “Recent progress in microstructured polymer optical fibre fabrication and characterisation,’ Opt. Fiber Techn. 9, 199–209 (2003).
    [CrossRef]
  4. B. Temelkuran, S.D. Hart, G. Benoit, J.D. Joannopoulos, Y. Fink, “Wavelength-scalable hollow optical fibres with large photonic bandgaps for CO2 laser transmission,” Nature 420, 650–653 (2002).
    [CrossRef] [PubMed]
  5. T. Katagiri, Y. Matsuura, M. Miyagi, “Photonic bandgap fiber with a silica core and multilayer dielectric cladding,” Opt. Lett. 29, 557–559 (2004).
    [CrossRef] [PubMed]
  6. B.J. Mangan, J.C. Knight, T.A. Birks, P.St.J. Russell, A.H. Greenaway, “Experimental study of dual-core photonic crystal fibre,” Electron. Lett. 36, 1358–1359 (2000).
    [CrossRef]
  7. B.H. Lee, J.B. Eom, J. Kim, D.S. Moon, U.-C. Paek, G.-H. Yang, “Photonic crystal fiber coupler,” Opt. Lett. 27, 812–814 (2002).
    [CrossRef]
  8. W.E.P. Padden, M.A. van Eijkelenborg, A. Argyros, N. A. Issa, “Coupling in a twin-core microstructured polymer optical fiber,” Appl. Phys. Lett. 84, 1689–1691 (2004).
    [CrossRef]
  9. H. Kim, J. Kim, U.-C. Paek, B.H. Lee, K. T. Kim, “Tunable photonic crystal fiber coupler based on a side-polishing technique,” Opt. Lett. 29, 1194–1196 (2004).
    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]
  11. K. Saitoh, M. Koshiba, “Leakage loss and group velocity dispersion in air-core photonic bandgap fibers,” Opt. Express 11, 3100 (2003).http://www.opticsexpress.org/abstract.cfm?URI=OPEX-11-23-3100
    [CrossRef] [PubMed]
  12. K. Saitoh, M. Koshiba, “Full-vectorial imaginary-distance beam propagation method based on a finite element scheme: application to photonic vrystal fibers,” J. Quantum Electron. 38, 927–933 (2002).
    [CrossRef]
  13. K. Saitoh, M. Koshiba, “Full-vectorial imaginary-distance beam propagation method with perfectly matched layers for anysotropic optical waveguides,” J. Ligthwave Techn. 19, 405–413 (2001).
    [CrossRef]
  14. M. Skorobogatiy, “Modeling the impact of imperfections in high-index-contrast photonic waveguides,” Phys. Rev. E 70, 46609 (2004).
    [CrossRef]
  15. M. Skorobogatiy, “Hollow Bragg fiber bundles: when coupling helps and when it hurts,” Opt. Lett. 29, 1479–1481 (2004).
    [CrossRef] [PubMed]

2004

2003

K. Saitoh, M. Koshiba, “Leakage loss and group velocity dispersion in air-core photonic bandgap fibers,” Opt. Express 11, 3100 (2003).http://www.opticsexpress.org/abstract.cfm?URI=OPEX-11-23-3100
[CrossRef] [PubMed]

C.M. Smith, N. Venkataraman, M.T. Gallagher, D. Muller, J.A. West, N.F. Borrelli, D.C. Allan, K.W. Koch, “Low-loss hollow-core silica/air photonic bandgap fibre,” Nature 424, 657–659 (2003).
[CrossRef] [PubMed]

P. Russell, ”Photonic crystal fibers,” Science 299, 358–362 (2003).
[CrossRef] [PubMed]

M.A. van Eijkelenborg, A. Argyros, G. Barton, I.M. Bassett, M. Fellew, G. Henry, N.A. Issa, M.C.J. Large, S. Manos, W. Padden, L. Poladian, J. Zagari, “Recent progress in microstructured polymer optical fibre fabrication and characterisation,’ Opt. Fiber Techn. 9, 199–209 (2003).
[CrossRef]

2002

B. Temelkuran, S.D. Hart, G. Benoit, J.D. Joannopoulos, Y. Fink, “Wavelength-scalable hollow optical fibres with large photonic bandgaps for CO2 laser transmission,” Nature 420, 650–653 (2002).
[CrossRef] [PubMed]

K. Saitoh, M. Koshiba, “Full-vectorial imaginary-distance beam propagation method based on a finite element scheme: application to photonic vrystal fibers,” J. Quantum Electron. 38, 927–933 (2002).
[CrossRef]

B.H. Lee, J.B. Eom, J. Kim, D.S. Moon, U.-C. Paek, G.-H. Yang, “Photonic crystal fiber coupler,” Opt. Lett. 27, 812–814 (2002).
[CrossRef]

2001

K. Saitoh, M. Koshiba, “Full-vectorial imaginary-distance beam propagation method with perfectly matched layers for anysotropic optical waveguides,” J. Ligthwave Techn. 19, 405–413 (2001).
[CrossRef]

2000

B.J. Mangan, J.C. Knight, T.A. Birks, P.St.J. Russell, A.H. Greenaway, “Experimental study of dual-core photonic crystal fibre,” Electron. Lett. 36, 1358–1359 (2000).
[CrossRef]

Allan, D.C.

C.M. Smith, N. Venkataraman, M.T. Gallagher, D. Muller, J.A. West, N.F. Borrelli, D.C. Allan, K.W. Koch, “Low-loss hollow-core silica/air photonic bandgap fibre,” Nature 424, 657–659 (2003).
[CrossRef] [PubMed]

Argyros, A.

W.E.P. Padden, M.A. van Eijkelenborg, A. Argyros, N. A. Issa, “Coupling in a twin-core microstructured polymer optical fiber,” Appl. Phys. Lett. 84, 1689–1691 (2004).
[CrossRef]

M.A. van Eijkelenborg, A. Argyros, G. Barton, I.M. Bassett, M. Fellew, G. Henry, N.A. Issa, M.C.J. Large, S. Manos, W. Padden, L. Poladian, J. Zagari, “Recent progress in microstructured polymer optical fibre fabrication and characterisation,’ Opt. Fiber Techn. 9, 199–209 (2003).
[CrossRef]

Bang, O.

Barton, G.

M.A. van Eijkelenborg, A. Argyros, G. Barton, I.M. Bassett, M. Fellew, G. Henry, N.A. Issa, M.C.J. Large, S. Manos, W. Padden, L. Poladian, J. Zagari, “Recent progress in microstructured polymer optical fibre fabrication and characterisation,’ Opt. Fiber Techn. 9, 199–209 (2003).
[CrossRef]

Bassett, I.M.

M.A. van Eijkelenborg, A. Argyros, G. Barton, I.M. Bassett, M. Fellew, G. Henry, N.A. Issa, M.C.J. Large, S. Manos, W. Padden, L. Poladian, J. Zagari, “Recent progress in microstructured polymer optical fibre fabrication and characterisation,’ Opt. Fiber Techn. 9, 199–209 (2003).
[CrossRef]

Benoit, G.

B. Temelkuran, S.D. Hart, G. Benoit, J.D. Joannopoulos, Y. Fink, “Wavelength-scalable hollow optical fibres with large photonic bandgaps for CO2 laser transmission,” Nature 420, 650–653 (2002).
[CrossRef] [PubMed]

Birks, T.A.

B.J. Mangan, J.C. Knight, T.A. Birks, P.St.J. Russell, A.H. Greenaway, “Experimental study of dual-core photonic crystal fibre,” Electron. Lett. 36, 1358–1359 (2000).
[CrossRef]

Bjarklev, A.

Borrelli, N.F.

C.M. Smith, N. Venkataraman, M.T. Gallagher, D. Muller, J.A. West, N.F. Borrelli, D.C. Allan, K.W. Koch, “Low-loss hollow-core silica/air photonic bandgap fibre,” Nature 424, 657–659 (2003).
[CrossRef] [PubMed]

Eom, J.B.

Fellew, M.

M.A. van Eijkelenborg, A. Argyros, G. Barton, I.M. Bassett, M. Fellew, G. Henry, N.A. Issa, M.C.J. Large, S. Manos, W. Padden, L. Poladian, J. Zagari, “Recent progress in microstructured polymer optical fibre fabrication and characterisation,’ Opt. Fiber Techn. 9, 199–209 (2003).
[CrossRef]

Fink, Y.

B. Temelkuran, S.D. Hart, G. Benoit, J.D. Joannopoulos, Y. Fink, “Wavelength-scalable hollow optical fibres with large photonic bandgaps for CO2 laser transmission,” Nature 420, 650–653 (2002).
[CrossRef] [PubMed]

Gallagher, M.T.

C.M. Smith, N. Venkataraman, M.T. Gallagher, D. Muller, J.A. West, N.F. Borrelli, D.C. Allan, K.W. Koch, “Low-loss hollow-core silica/air photonic bandgap fibre,” Nature 424, 657–659 (2003).
[CrossRef] [PubMed]

Greenaway, A.H.

B.J. Mangan, J.C. Knight, T.A. Birks, P.St.J. Russell, A.H. Greenaway, “Experimental study of dual-core photonic crystal fibre,” Electron. Lett. 36, 1358–1359 (2000).
[CrossRef]

Hart, S.D.

B. Temelkuran, S.D. Hart, G. Benoit, J.D. Joannopoulos, Y. Fink, “Wavelength-scalable hollow optical fibres with large photonic bandgaps for CO2 laser transmission,” Nature 420, 650–653 (2002).
[CrossRef] [PubMed]

Henry, G.

M.A. van Eijkelenborg, A. Argyros, G. Barton, I.M. Bassett, M. Fellew, G. Henry, N.A. Issa, M.C.J. Large, S. Manos, W. Padden, L. Poladian, J. Zagari, “Recent progress in microstructured polymer optical fibre fabrication and characterisation,’ Opt. Fiber Techn. 9, 199–209 (2003).
[CrossRef]

Issa, N. A.

W.E.P. Padden, M.A. van Eijkelenborg, A. Argyros, N. A. Issa, “Coupling in a twin-core microstructured polymer optical fiber,” Appl. Phys. Lett. 84, 1689–1691 (2004).
[CrossRef]

Issa, N.A.

M.A. van Eijkelenborg, A. Argyros, G. Barton, I.M. Bassett, M. Fellew, G. Henry, N.A. Issa, M.C.J. Large, S. Manos, W. Padden, L. Poladian, J. Zagari, “Recent progress in microstructured polymer optical fibre fabrication and characterisation,’ Opt. Fiber Techn. 9, 199–209 (2003).
[CrossRef]

Joannopoulos, J.D.

B. Temelkuran, S.D. Hart, G. Benoit, J.D. Joannopoulos, Y. Fink, “Wavelength-scalable hollow optical fibres with large photonic bandgaps for CO2 laser transmission,” Nature 420, 650–653 (2002).
[CrossRef] [PubMed]

Katagiri, T.

Kim, H.

Kim, J.

Kim, K. T.

Knight, J.C.

B.J. Mangan, J.C. Knight, T.A. Birks, P.St.J. Russell, A.H. Greenaway, “Experimental study of dual-core photonic crystal fibre,” Electron. Lett. 36, 1358–1359 (2000).
[CrossRef]

Koch, K.W.

C.M. Smith, N. Venkataraman, M.T. Gallagher, D. Muller, J.A. West, N.F. Borrelli, D.C. Allan, K.W. Koch, “Low-loss hollow-core silica/air photonic bandgap fibre,” Nature 424, 657–659 (2003).
[CrossRef] [PubMed]

Koshiba, M.

K. Saitoh, M. Koshiba, “Leakage loss and group velocity dispersion in air-core photonic bandgap fibers,” Opt. Express 11, 3100 (2003).http://www.opticsexpress.org/abstract.cfm?URI=OPEX-11-23-3100
[CrossRef] [PubMed]

K. Saitoh, M. Koshiba, “Full-vectorial imaginary-distance beam propagation method based on a finite element scheme: application to photonic vrystal fibers,” J. Quantum Electron. 38, 927–933 (2002).
[CrossRef]

K. Saitoh, M. Koshiba, “Full-vectorial imaginary-distance beam propagation method with perfectly matched layers for anysotropic optical waveguides,” J. Ligthwave Techn. 19, 405–413 (2001).
[CrossRef]

Laegsgaard, J.

Large, M.C.J.

M.A. van Eijkelenborg, A. Argyros, G. Barton, I.M. Bassett, M. Fellew, G. Henry, N.A. Issa, M.C.J. Large, S. Manos, W. Padden, L. Poladian, J. Zagari, “Recent progress in microstructured polymer optical fibre fabrication and characterisation,’ Opt. Fiber Techn. 9, 199–209 (2003).
[CrossRef]

Lee, B.H.

Mangan, B.J.

B.J. Mangan, J.C. Knight, T.A. Birks, P.St.J. Russell, A.H. Greenaway, “Experimental study of dual-core photonic crystal fibre,” Electron. Lett. 36, 1358–1359 (2000).
[CrossRef]

Manos, S.

M.A. van Eijkelenborg, A. Argyros, G. Barton, I.M. Bassett, M. Fellew, G. Henry, N.A. Issa, M.C.J. Large, S. Manos, W. Padden, L. Poladian, J. Zagari, “Recent progress in microstructured polymer optical fibre fabrication and characterisation,’ Opt. Fiber Techn. 9, 199–209 (2003).
[CrossRef]

Matsuura, Y.

Miyagi, M.

Moon, D.S.

Muller, D.

C.M. Smith, N. Venkataraman, M.T. Gallagher, D. Muller, J.A. West, N.F. Borrelli, D.C. Allan, K.W. Koch, “Low-loss hollow-core silica/air photonic bandgap fibre,” Nature 424, 657–659 (2003).
[CrossRef] [PubMed]

Padden, W.

M.A. van Eijkelenborg, A. Argyros, G. Barton, I.M. Bassett, M. Fellew, G. Henry, N.A. Issa, M.C.J. Large, S. Manos, W. Padden, L. Poladian, J. Zagari, “Recent progress in microstructured polymer optical fibre fabrication and characterisation,’ Opt. Fiber Techn. 9, 199–209 (2003).
[CrossRef]

Padden, W.E.P.

W.E.P. Padden, M.A. van Eijkelenborg, A. Argyros, N. A. Issa, “Coupling in a twin-core microstructured polymer optical fiber,” Appl. Phys. Lett. 84, 1689–1691 (2004).
[CrossRef]

Paek, U.-C.

Poladian, L.

M.A. van Eijkelenborg, A. Argyros, G. Barton, I.M. Bassett, M. Fellew, G. Henry, N.A. Issa, M.C.J. Large, S. Manos, W. Padden, L. Poladian, J. Zagari, “Recent progress in microstructured polymer optical fibre fabrication and characterisation,’ Opt. Fiber Techn. 9, 199–209 (2003).
[CrossRef]

Russell, P.

P. Russell, ”Photonic crystal fibers,” Science 299, 358–362 (2003).
[CrossRef] [PubMed]

Russell, P.St.J.

B.J. Mangan, J.C. Knight, T.A. Birks, P.St.J. Russell, A.H. Greenaway, “Experimental study of dual-core photonic crystal fibre,” Electron. Lett. 36, 1358–1359 (2000).
[CrossRef]

Saitoh, K.

K. Saitoh, M. Koshiba, “Leakage loss and group velocity dispersion in air-core photonic bandgap fibers,” Opt. Express 11, 3100 (2003).http://www.opticsexpress.org/abstract.cfm?URI=OPEX-11-23-3100
[CrossRef] [PubMed]

K. Saitoh, M. Koshiba, “Full-vectorial imaginary-distance beam propagation method based on a finite element scheme: application to photonic vrystal fibers,” J. Quantum Electron. 38, 927–933 (2002).
[CrossRef]

K. Saitoh, M. Koshiba, “Full-vectorial imaginary-distance beam propagation method with perfectly matched layers for anysotropic optical waveguides,” J. Ligthwave Techn. 19, 405–413 (2001).
[CrossRef]

Skorobogatiy, M.

M. Skorobogatiy, “Modeling the impact of imperfections in high-index-contrast photonic waveguides,” Phys. Rev. E 70, 46609 (2004).
[CrossRef]

M. Skorobogatiy, “Hollow Bragg fiber bundles: when coupling helps and when it hurts,” Opt. Lett. 29, 1479–1481 (2004).
[CrossRef] [PubMed]

Smith, C.M.

C.M. Smith, N. Venkataraman, M.T. Gallagher, D. Muller, J.A. West, N.F. Borrelli, D.C. Allan, K.W. Koch, “Low-loss hollow-core silica/air photonic bandgap fibre,” Nature 424, 657–659 (2003).
[CrossRef] [PubMed]

Temelkuran, B.

B. Temelkuran, S.D. Hart, G. Benoit, J.D. Joannopoulos, Y. Fink, “Wavelength-scalable hollow optical fibres with large photonic bandgaps for CO2 laser transmission,” Nature 420, 650–653 (2002).
[CrossRef] [PubMed]

van Eijkelenborg, M.A.

W.E.P. Padden, M.A. van Eijkelenborg, A. Argyros, N. A. Issa, “Coupling in a twin-core microstructured polymer optical fiber,” Appl. Phys. Lett. 84, 1689–1691 (2004).
[CrossRef]

M.A. van Eijkelenborg, A. Argyros, G. Barton, I.M. Bassett, M. Fellew, G. Henry, N.A. Issa, M.C.J. Large, S. Manos, W. Padden, L. Poladian, J. Zagari, “Recent progress in microstructured polymer optical fibre fabrication and characterisation,’ Opt. Fiber Techn. 9, 199–209 (2003).
[CrossRef]

Venkataraman, N.

C.M. Smith, N. Venkataraman, M.T. Gallagher, D. Muller, J.A. West, N.F. Borrelli, D.C. Allan, K.W. Koch, “Low-loss hollow-core silica/air photonic bandgap fibre,” Nature 424, 657–659 (2003).
[CrossRef] [PubMed]

West, J.A.

C.M. Smith, N. Venkataraman, M.T. Gallagher, D. Muller, J.A. West, N.F. Borrelli, D.C. Allan, K.W. Koch, “Low-loss hollow-core silica/air photonic bandgap fibre,” Nature 424, 657–659 (2003).
[CrossRef] [PubMed]

Yang, G.-H.

Zagari, J.

M.A. van Eijkelenborg, A. Argyros, G. Barton, I.M. Bassett, M. Fellew, G. Henry, N.A. Issa, M.C.J. Large, S. Manos, W. Padden, L. Poladian, J. Zagari, “Recent progress in microstructured polymer optical fibre fabrication and characterisation,’ Opt. Fiber Techn. 9, 199–209 (2003).
[CrossRef]

Appl. Phys. Lett.

W.E.P. Padden, M.A. van Eijkelenborg, A. Argyros, N. A. Issa, “Coupling in a twin-core microstructured polymer optical fiber,” Appl. Phys. Lett. 84, 1689–1691 (2004).
[CrossRef]

Electron. Lett.

B.J. Mangan, J.C. Knight, T.A. Birks, P.St.J. Russell, A.H. Greenaway, “Experimental study of dual-core photonic crystal fibre,” Electron. Lett. 36, 1358–1359 (2000).
[CrossRef]

J. Ligthwave Techn.

K. Saitoh, M. Koshiba, “Full-vectorial imaginary-distance beam propagation method with perfectly matched layers for anysotropic optical waveguides,” J. Ligthwave Techn. 19, 405–413 (2001).
[CrossRef]

J. Quantum Electron.

K. Saitoh, M. Koshiba, “Full-vectorial imaginary-distance beam propagation method based on a finite element scheme: application to photonic vrystal fibers,” J. Quantum Electron. 38, 927–933 (2002).
[CrossRef]

Nature

C.M. Smith, N. Venkataraman, M.T. Gallagher, D. Muller, J.A. West, N.F. Borrelli, D.C. Allan, K.W. Koch, “Low-loss hollow-core silica/air photonic bandgap fibre,” Nature 424, 657–659 (2003).
[CrossRef] [PubMed]

B. Temelkuran, S.D. Hart, G. Benoit, J.D. Joannopoulos, Y. Fink, “Wavelength-scalable hollow optical fibres with large photonic bandgaps for CO2 laser transmission,” Nature 420, 650–653 (2002).
[CrossRef] [PubMed]

Opt. Express

Opt. Fiber Techn.

M.A. van Eijkelenborg, A. Argyros, G. Barton, I.M. Bassett, M. Fellew, G. Henry, N.A. Issa, M.C.J. Large, S. Manos, W. Padden, L. Poladian, J. Zagari, “Recent progress in microstructured polymer optical fibre fabrication and characterisation,’ Opt. Fiber Techn. 9, 199–209 (2003).
[CrossRef]

Opt. Lett.

Phys. Rev. E

M. Skorobogatiy, “Modeling the impact of imperfections in high-index-contrast photonic waveguides,” Phys. Rev. E 70, 46609 (2004).
[CrossRef]

Science

P. Russell, ”Photonic crystal fibers,” Science 299, 358–362 (2003).
[CrossRef] [PubMed]

Supplementary Material (1)

» Media 1: AVI (2733 KB)     

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Figures (7)

Fig. 1.
Fig. 1.

Schematic of a two hollow core MOF coupler. Cores are separated by N lattice periods. Transverse waveguide is formed by the holes of somewhat different diameters placed along the inter-core line. Holes closest to the cores are not modified.

Fig. 2.
Fig. 2.

a) Proximity coupling between the modes of two cores separated by 4 periods, dispersion relations, coupling length. b) Proximity coupling length as a function of λ for various inter-core separations.

Fig. 3.
Fig. 3.

Resonant coupling between the modes of two cores separated by 4 periods mediated by a line defect. a) Upper plot: dispersion relations of the supermodes exhibiting avoiding crossing with the transverse waveguide modes. Lower plot: coupling length, losses. b) Field distribution of a y - even supermode at λ = 13052μm resonance. Excitation of a localized mode of a line defect is observed in an inter-core region.

Fig. 4.
Fig. 4.

Resonant coupling between the modes of two cores separated by 11 periods mediated by a line defect. a) Upper plot: dispersion relations of the supermodes exhibit avoiding crossing with waveguide modes. Lower plot: coupling length from the modal analysis (solid) and BPM (solid with circles), losses from the modal analysis (dashed) and BPM (dashed with circles). b) Field distribution of a y - even supermode at the λ = 1.3064μm resonance. Excitation of a localized line defect mode is observed in the inter-core region. [Media 1]

Fig. 5.
Fig. 5.

Field distribution of the supermodes at the consecutive resonances for N = 11. The number of spatial oscillations in the inter-core region increases towards shorter wavelengths signifying Fabry-Perot nature of the localized states in a transverse waveguide.

Fig. 6.
Fig. 6.

Coupling length across the band gap as a function of the inter-core separation N. Left: at resonances coupling length is on the order of several millimeters regardless of the inter-core separation, at longer wavelength coupling is dominated by the proximity interaction. Right: Fabry-Perot like resonances. Spectral separation between the resonances decreases with an increasing inter-core distance.

Fig. 7.
Fig. 7.

Coupling length across the band gap as a function of the line defect length N, mode polarization and defect type.

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