Abstract

We model and demonstrate a simple mode selective all-fiber coupler capable of exciting specific higher order modes in two- and few-mode fibres with high efficiency and purity. The coupler is based on inter-modally phase-matching the propagation constants in each arm of the asymmetric fused coupler, formed by dissimilar fibres. At a specific coupler diameter, the launched fundamental LP01 mode is coupled into the higher order mode (LP11, LP21, LP02) in the other arm, over a broadband wave-length range around 1550 nm. Unlike other techniques, the demonstrated coupler is composed of a multimode fiber that is weakly fused with a phase matched conventional single mode telecom fiber (SMF-28). The beating between the supermodes at the coupler waist produces a periodic power transfer between the two arms, and therefore, by monitoring the beating while tapering, it is possible to obtain optimum selection for the desired mode. High coupling efficiencies in excess of 90% for all the higher order modes were recorded over 100 nm spectral range, while insertion losses remain as low as 0.5 dB. Coupling efficiency can be further enhanced by performing slow tapering at high temperature, in order to precisely control the coupler cross-section geometry.

© 2014 Optical Society of America

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References

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  1. D. J. Richardson, J. M. Fini, L. E. Nelson, “Space-division multiplexing in optical fibres,” Nat. Photonics 7, 354–362 (2013).
    [CrossRef]
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    [CrossRef]
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    [CrossRef] [PubMed]
  4. S. Leon-Saval, A. Argyros, J. Bland-Hawthorn, “Photonic lanterns: a study of light propagation in multimode to single-mode converters,” Opt. Express 18, 8430–8439 (2010).
    [CrossRef] [PubMed]
  5. S. Leon-Saval, N. Fontaine, J. Salazar-Gil, B. Ercan, R. Ryf, J. Bland-Hawthorn, “Mode-selective photonic lanterns for space-division multiplexing,” Opt. Express 22, 1036–1044 (2014).
    [CrossRef] [PubMed]
  6. N. K. Fontaine, S. G. Leon-Saval, R. Ryf, J. R. S. Gil, B. Ercan, J. Bland-Hawthorn, “Mode-selective dissimilar fiber photonic-lantern spatial multiplexers for few-mode fiber,” Optical Communication (ECOC 2013), 39th European Conference and Exhibition, pp. 1, 3, 22–26 Sept. 2013
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    [CrossRef] [PubMed]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef] [PubMed]
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  18. K. Y. Song, I. K. Hwang, S. H. Yun, B. Y. Kim, “High performance fused-type mode-selective coupler using elliptical core two-mode fiber at 1550nm,” IEEE Photon. Technol. Lett. 14, 501–503 (2002).
    [CrossRef]
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2014 (2)

2013 (2)

2012 (1)

2010 (2)

2005 (1)

2002 (1)

K. Y. Song, I. K. Hwang, S. H. Yun, B. Y. Kim, “High performance fused-type mode-selective coupler using elliptical core two-mode fiber at 1550nm,” IEEE Photon. Technol. Lett. 14, 501–503 (2002).
[CrossRef]

1999 (1)

Y. Shou, J. Bures, S. Lacroix, X. Daxhelet, “Mode separation in fused fiber coupler made of two-mode fibers,” Opt. Fiber Technol. 5, 92–104 (1999).
[CrossRef]

1997 (1)

M. Vaziri, C. Chen, “An etched two-mode fiber modal coupling element,” J. Lightwave Technol. 15, 474–481 (1997).
[CrossRef]

1995 (1)

1994 (1)

1992 (1)

1991 (2)

A. M. Vengsarkar, J. A. Greene, K. A. Murphy, “Photoinduced refractive-index changes in two-mode elliptical-core fibers: sensing applications,” Opt. Lett. 16, 1541–1543 (1991).
[CrossRef] [PubMed]

C. D. Poole, C. D. Townsend, K. T. Nelson, “Helical-grating two-mode fiber spatial-mode coupler,” J. Light-waveTechnol. 9, 598–604 (1991).
[CrossRef]

1990 (1)

S. Y. Haung, J. N. Blake, B. Y. Kim, “Perturbation effects on mode propagation in highly elliptical core two-mode fibers,” J. Lightwave Technol. 8, 23–33 (1990).
[CrossRef]

1989 (1)

H. G. Park, B. Y. Kim, “Intermodal coupler using permanently photoinduced grating in two-modeoptical fiber,” Electron. Lett. 25, 797–799 (1989).
[CrossRef]

1987 (2)

1986 (1)

1985 (2)

A. W. Snyder, X. H. Zheng, “Fused couplers of arbitrary cross-section,” Electron. Lett. 21, 1079–1080 (1985).
[CrossRef]

F. P. Payne, C. D. Hussey, M. S. Yataki, “Polarisation analysis of strongly fused and weakly fused tapered couplers,” Electron. Lett. 21, 561–563 (1985).
[CrossRef]

1984 (1)

Alam, S.

Argyros, A.

Birks, T.

Blake, J. N.

S. Y. Haung, J. N. Blake, B. Y. Kim, “Perturbation effects on mode propagation in highly elliptical core two-mode fibers,” J. Lightwave Technol. 8, 23–33 (1990).
[CrossRef]

J. N. Blake, S. U. Huang, B. Y. Kim, H. J. Shaw, “Strain effects on highly elliptical core two-mode fibers,” Opt. Lett. 12, 732–734 (1987).
[CrossRef] [PubMed]

Bland-Hawthorn, J.

Bolle, C.

Brambilla, G.

Brooks, J. L.

Bures, J.

Y. Shou, J. Bures, S. Lacroix, X. Daxhelet, “Mode separation in fused fiber coupler made of two-mode fibers,” Opt. Fiber Technol. 5, 92–104 (1999).
[CrossRef]

S. Lacroix, F. Gonthier, J. Bures, “Modeling of symmetric 2× 2 fused-fiber couplers,” Appl. Opt. 33, 8361–8369 (1994).
[CrossRef] [PubMed]

Burrows, E. C.

Carneiro, S. R. M.

Carrara, S. L. A.

Castro, F. A.

Chang, H.

Chen, C.

M. Vaziri, C. Chen, “An etched two-mode fiber modal coupling element,” J. Lightwave Technol. 15, 474–481 (1997).
[CrossRef]

Chen, R.

Chiang, K.

Daxhelet, X.

Y. Shou, J. Bures, S. Lacroix, X. Daxhelet, “Mode separation in fused fiber coupler made of two-mode fibers,” Opt. Fiber Technol. 5, 92–104 (1999).
[CrossRef]

Englund, M.

Ercan, B.

S. Leon-Saval, N. Fontaine, J. Salazar-Gil, B. Ercan, R. Ryf, J. Bland-Hawthorn, “Mode-selective photonic lanterns for space-division multiplexing,” Opt. Express 22, 1036–1044 (2014).
[CrossRef] [PubMed]

N. K. Fontaine, S. G. Leon-Saval, R. Ryf, J. R. S. Gil, B. Ercan, J. Bland-Hawthorn, “Mode-selective dissimilar fiber photonic-lantern spatial multiplexers for few-mode fiber,” Optical Communication (ECOC 2013), 39th European Conference and Exhibition, pp. 1, 3, 22–26 Sept. 2013

Esmaeelpour, M.

Essiambre, R.

Fini, J. M.

D. J. Richardson, J. M. Fini, L. E. Nelson, “Space-division multiplexing in optical fibres,” Nat. Photonics 7, 354–362 (2013).
[CrossRef]

Fontaine, N.

Fontaine, N. K.

N. K. Fontaine, S. G. Leon-Saval, R. Ryf, J. R. S. Gil, B. Ercan, J. Bland-Hawthorn, “Mode-selective dissimilar fiber photonic-lantern spatial multiplexers for few-mode fiber,” Optical Communication (ECOC 2013), 39th European Conference and Exhibition, pp. 1, 3, 22–26 Sept. 2013

Gil, J. R. S.

N. K. Fontaine, S. G. Leon-Saval, R. Ryf, J. R. S. Gil, B. Ercan, J. Bland-Hawthorn, “Mode-selective dissimilar fiber photonic-lantern spatial multiplexers for few-mode fiber,” Optical Communication (ECOC 2013), 39th European Conference and Exhibition, pp. 1, 3, 22–26 Sept. 2013

Giles, I.

Gnauck, A. H.

Gonthier, F.

Greene, J. A.

Gris-Sánchez, I.

Haung, S. Y.

S. Y. Haung, J. N. Blake, B. Y. Kim, “Perturbation effects on mode propagation in highly elliptical core two-mode fibers,” J. Lightwave Technol. 8, 23–33 (1990).
[CrossRef]

Huang, S. U.

Hussey, C. D.

F. P. Payne, C. D. Hussey, M. S. Yataki, “Polarisation analysis of strongly fused and weakly fused tapered couplers,” Electron. Lett. 21, 561–563 (1985).
[CrossRef]

Hwang, I. K.

K. Y. Song, I. K. Hwang, S. H. Yun, B. Y. Kim, “High performance fused-type mode-selective coupler using elliptical core two-mode fiber at 1550nm,” IEEE Photon. Technol. Lett. 14, 501–503 (2002).
[CrossRef]

K. Y. Song, I. K. Hwang, S. H. Yun, B. Y. Kim, “High performance fused-type mode selective coupler for two-mode fiber devices,” in Opt. Fibre Commun. Conf., Baltimore, 7–10 Mar (2000).

Ismaeel, R.

Jung, Y.

Kim, B. Y.

K. Y. Song, I. K. Hwang, S. H. Yun, B. Y. Kim, “High performance fused-type mode-selective coupler using elliptical core two-mode fiber at 1550nm,” IEEE Photon. Technol. Lett. 14, 501–503 (2002).
[CrossRef]

S. Y. Haung, J. N. Blake, B. Y. Kim, “Perturbation effects on mode propagation in highly elliptical core two-mode fibers,” J. Lightwave Technol. 8, 23–33 (1990).
[CrossRef]

H. G. Park, B. Y. Kim, “Intermodal coupler using permanently photoinduced grating in two-modeoptical fiber,” Electron. Lett. 25, 797–799 (1989).
[CrossRef]

J. N. Blake, S. U. Huang, B. Y. Kim, H. J. Shaw, “Strain effects on highly elliptical core two-mode fibers,” Opt. Lett. 12, 732–734 (1987).
[CrossRef] [PubMed]

W. V. Sorin, B. Y. Kim, H. J. Shaw, “Highly selective evanescent modal filter for two-mode optical fibers,” Opt. Lett. 11, 581–583 (1986).
[CrossRef] [PubMed]

K. Y. Song, I. K. Hwang, S. H. Yun, B. Y. Kim, “High performance fused-type mode selective coupler for two-mode fiber devices,” in Opt. Fibre Commun. Conf., Baltimore, 7–10 Mar (2000).

Lacroix, S.

Y. Shou, J. Bures, S. Lacroix, X. Daxhelet, “Mode separation in fused fiber coupler made of two-mode fibers,” Opt. Fiber Technol. 5, 92–104 (1999).
[CrossRef]

S. Lacroix, F. Gonthier, J. Bures, “Modeling of symmetric 2× 2 fused-fiber couplers,” Appl. Opt. 33, 8361–8369 (1994).
[CrossRef] [PubMed]

Leon-Saval, S.

Leon-Saval, S. G.

N. K. Fontaine, S. G. Leon-Saval, R. Ryf, J. R. S. Gil, B. Ercan, J. Bland-Hawthorn, “Mode-selective dissimilar fiber photonic-lantern spatial multiplexers for few-mode fiber,” Optical Communication (ECOC 2013), 39th European Conference and Exhibition, pp. 1, 3, 22–26 Sept. 2013

Lin, T.

Lingle, R.

Lisboa, O.

McCurdy, A. H.

Mumtaz, S.

Murphy, K. A.

Nelson, K. T.

C. D. Poole, C. D. Townsend, K. T. Nelson, “Helical-grating two-mode fiber spatial-mode coupler,” J. Light-waveTechnol. 9, 598–604 (1991).
[CrossRef]

Nelson, L. E.

D. J. Richardson, J. M. Fini, L. E. Nelson, “Space-division multiplexing in optical fibres,” Nat. Photonics 7, 354–362 (2013).
[CrossRef]

Park, H. G.

H. G. Park, B. Y. Kim, “Intermodal coupler using permanently photoinduced grating in two-modeoptical fiber,” Electron. Lett. 25, 797–799 (1989).
[CrossRef]

Payne, F. P.

F. P. Payne, C. D. Hussey, M. S. Yataki, “Polarisation analysis of strongly fused and weakly fused tapered couplers,” Electron. Lett. 21, 561–563 (1985).
[CrossRef]

Peckham, D. W.

Poole, C. D.

C. D. Poole, C. D. Townsend, K. T. Nelson, “Helical-grating two-mode fiber spatial-mode coupler,” J. Light-waveTechnol. 9, 598–604 (1991).
[CrossRef]

Randel, S.

Richardson, D.

Richardson, D. J.

D. J. Richardson, J. M. Fini, L. E. Nelson, “Space-division multiplexing in optical fibres,” Nat. Photonics 7, 354–362 (2013).
[CrossRef]

Ryf, R.

Salazar-Gil, J.

Shaw, H. J.

Shou, Y.

Y. Shou, J. Bures, S. Lacroix, X. Daxhelet, “Mode separation in fused fiber coupler made of two-mode fibers,” Opt. Fiber Technol. 5, 92–104 (1999).
[CrossRef]

Sierra, A.

Snyder, A. W.

A. W. Snyder, X. H. Zheng, “Fused couplers of arbitrary cross-section,” Electron. Lett. 21, 1079–1080 (1985).
[CrossRef]

Song, K. Y.

K. Y. Song, I. K. Hwang, S. H. Yun, B. Y. Kim, “High performance fused-type mode-selective coupler using elliptical core two-mode fiber at 1550nm,” IEEE Photon. Technol. Lett. 14, 501–503 (2002).
[CrossRef]

K. Y. Song, I. K. Hwang, S. H. Yun, B. Y. Kim, “High performance fused-type mode selective coupler for two-mode fiber devices,” in Opt. Fibre Commun. Conf., Baltimore, 7–10 Mar (2000).

Sorin, W. V.

Townsend, C. D.

C. D. Poole, C. D. Townsend, K. T. Nelson, “Helical-grating two-mode fiber spatial-mode coupler,” J. Light-waveTechnol. 9, 598–604 (1991).
[CrossRef]

Vaziri, M.

M. Vaziri, C. Chen, “An etched two-mode fiber modal coupling element,” J. Lightwave Technol. 15, 474–481 (1997).
[CrossRef]

Vengsarkar, A. M.

Winzer, P. J.

Wu, T.

Yataki, M. S.

F. P. Payne, C. D. Hussey, M. S. Yataki, “Polarisation analysis of strongly fused and weakly fused tapered couplers,” Electron. Lett. 21, 561–563 (1985).
[CrossRef]

Yerolatsitis, S.

Youngquist, R. C.

Yun, S. H.

K. Y. Song, I. K. Hwang, S. H. Yun, B. Y. Kim, “High performance fused-type mode-selective coupler using elliptical core two-mode fiber at 1550nm,” IEEE Photon. Technol. Lett. 14, 501–503 (2002).
[CrossRef]

K. Y. Song, I. K. Hwang, S. H. Yun, B. Y. Kim, “High performance fused-type mode selective coupler for two-mode fiber devices,” in Opt. Fibre Commun. Conf., Baltimore, 7–10 Mar (2000).

Zheng, X. H.

A. W. Snyder, X. H. Zheng, “Fused couplers of arbitrary cross-section,” Electron. Lett. 21, 1079–1080 (1985).
[CrossRef]

Appl. Opt. (2)

Electron. Lett. (3)

A. W. Snyder, X. H. Zheng, “Fused couplers of arbitrary cross-section,” Electron. Lett. 21, 1079–1080 (1985).
[CrossRef]

F. P. Payne, C. D. Hussey, M. S. Yataki, “Polarisation analysis of strongly fused and weakly fused tapered couplers,” Electron. Lett. 21, 561–563 (1985).
[CrossRef]

H. G. Park, B. Y. Kim, “Intermodal coupler using permanently photoinduced grating in two-modeoptical fiber,” Electron. Lett. 25, 797–799 (1989).
[CrossRef]

IEEE Photon. Technol. Lett. (1)

K. Y. Song, I. K. Hwang, S. H. Yun, B. Y. Kim, “High performance fused-type mode-selective coupler using elliptical core two-mode fiber at 1550nm,” IEEE Photon. Technol. Lett. 14, 501–503 (2002).
[CrossRef]

J. Light-waveTechnol. (1)

C. D. Poole, C. D. Townsend, K. T. Nelson, “Helical-grating two-mode fiber spatial-mode coupler,” J. Light-waveTechnol. 9, 598–604 (1991).
[CrossRef]

J. Lightwave Technol. (3)

R. Ryf, S. Randel, A. H. Gnauck, C. Bolle, A. Sierra, S. Mumtaz, M. Esmaeelpour, E. C. Burrows, R. Essiambre, P. J. Winzer, D. W. Peckham, A. H. McCurdy, R. Lingle, “Mode-division multiplexing over 96 km of few-mode fiber using coherent 6 × 6 MIMO processing,” J. Lightwave Technol. 30, 521–531 (2012).
[CrossRef]

S. Y. Haung, J. N. Blake, B. Y. Kim, “Perturbation effects on mode propagation in highly elliptical core two-mode fibers,” J. Lightwave Technol. 8, 23–33 (1990).
[CrossRef]

M. Vaziri, C. Chen, “An etched two-mode fiber modal coupling element,” J. Lightwave Technol. 15, 474–481 (1997).
[CrossRef]

J. Opt. (1)

G. Brambilla, “Optical fiber nanowires and microwires: a review,” J. Opt. 12, 043001 (2010).
[CrossRef]

Nat. Photonics (1)

D. J. Richardson, J. M. Fini, L. E. Nelson, “Space-division multiplexing in optical fibres,” Nat. Photonics 7, 354–362 (2013).
[CrossRef]

Opt. Express (4)

Opt. Fiber Technol. (1)

Y. Shou, J. Bures, S. Lacroix, X. Daxhelet, “Mode separation in fused fiber coupler made of two-mode fibers,” Opt. Fiber Technol. 5, 92–104 (1999).
[CrossRef]

Opt. Lett. (7)

Other (2)

K. Y. Song, I. K. Hwang, S. H. Yun, B. Y. Kim, “High performance fused-type mode selective coupler for two-mode fiber devices,” in Opt. Fibre Commun. Conf., Baltimore, 7–10 Mar (2000).

N. K. Fontaine, S. G. Leon-Saval, R. Ryf, J. R. S. Gil, B. Ercan, J. Bland-Hawthorn, “Mode-selective dissimilar fiber photonic-lantern spatial multiplexers for few-mode fiber,” Optical Communication (ECOC 2013), 39th European Conference and Exhibition, pp. 1, 3, 22–26 Sept. 2013

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Figures (7)

Fig. 1
Fig. 1

Schematic of the MSC: light is launched in the SMF port; the LP11 is expected to be preferentially excited at the TMF output port, while the uncoupled fundamental LP01 will propagate along the SMF. For the FMF, it is possible to select any of the modes that propagates in the FMF by choosing the SMF pre-tapering diameter.

Fig. 2
Fig. 2

(a) The electric field component (x direction) of the phase matched modes LP01 in the SMF port and the LP11 in the TMF port.(b) the phase matching graphs for the LP01 in the SMF and the LP11 in the TMF. (c) The electric field component of the LP01 in the SMF and the LP11, LP21, LP02 in the FMF port. (d) The effective index matching graph for the LP01 in the SMF and the desired mode in the FMF (all the modelling was performed using geometrical parameters obtained experimentally, The dotted line represents the dimensions chosen for the fabricated coupler.)

Fig. 3
Fig. 3

(a) Scanning electron microscope image of the weakly fused coupler cross section. (b) Simulated resulted for specific coupler diameter, most of the power is expected to be transferred to the output of the coupler as LP11.

Fig. 4
Fig. 4

(a) Coupling efficiency versus the deviation from the ideal SMF phase matching diameter at the coupler waist, r1 is the ideal SMF diameter and r2 represents smaller or larger diameter than the ideal diameter(b) The electric field amplitude ratio at the fibre centres, |E2|/|E1|, versus the ratio between both fibres propagation constants β1/β2.

Fig. 5
Fig. 5

(a) Power transfer between the two arms of the coupler against pulling length: a periodic power transfer between the output ports is observed. (b) Output spectra of the two arms of the coupler. Far field images of the MSC output at λ ≈1550 nm from the (c) TMF port and (d) SMF port.

Fig. 6
Fig. 6

Power transfer between the two arms of the coupler against pulling length for the (a) LP11, (c) LP21, (e) LP02 modes. Output spectra of the two arms of the coupler for the (b) LP11, (d) LP21, (f) LP02 modes.

Fig. 7
Fig. 7

CCD images of the LP11, LP21 and LP02 modes excited in the FMF at different launching wavelengths.

Equations (1)

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d d z ( A 1 ( z ) A 2 ( z ) ) = ( i Δ β 2 i κ i κ i Δ β 2 ) ( A 1 ( z ) A 2 ( z ) )

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