Abstract

Optical fibers have become ubiquitous tools for the creation, propagation, manipulation, and detection of light. However, while the intensity of light propagating through the fiber can increase or decrease along the length through amplification or attenuation, respectively, the properties of the fiber itself generally do not, thus removing an opportunity to further control the behavior of light and performance of fiber-based devices. Shown here are optical fibers that exhibit significant changes in their longitudinal optical properties, specifically a tailored longitudinal numerical aperture change of about 12% over less than 20 meters of length. This is about 1900 times greater than previously reported. The Brillouin gain coefficient was found to decrease by over 6 dB relative to a standard commercial single mode fiber. Next generation analogs are expected to exhibit more than a 10 dB reduction in SBS gain using larger, yet still reasonably manufacturable gradients over practical lengths.

© 2012 OSA

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References

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  1. V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
    [CrossRef]
  2. J. Hansryd, F. Dross, M. Westlund, P. Andrekson, and S. Knudsen, “Increase of the SBS threshold in a short highly nonlinear fiber by applying a temperature distribution,” J. Lightwave Technol. 19(11), 1691–1697 (2001).
    [CrossRef]
  3. N. Yoshizawa, T. Horiguchi, and T. Kurashima, “Proposal for stimulated Brillouin-scattering suppression by fiber cabling,” Electron. Lett. 27(12), 1100–1101 (1991).
    [CrossRef]
  4. M. Li, S. Li, and D. Nolan, “Nonlinear fibers for signal processing using optical Kerr effects,” J. Lightwave Technol. 23(11), 3606–3614 (2005).
    [CrossRef]
  5. J. Boggio, J. Marconi, and F. Fragnito, “Experimental and numerical investigation of the SBS-threshold increase in an optical fiber by applying strain distributions,” J. Lightwave Technol. 23(11), 3808–3814 (2005).
    [CrossRef]
  6. K. Nakajima, M. Ohashi, K. Shiraki, T. Horiguchi, K. Kurokawa, and Y. Miyajima, “Four-wave mixing suppression effect of dispersion distributed fibers,” J. Lightwave Technol. 17(10), 1814–1822 (1999).
    [CrossRef]
  7. R. Stolen, “Polarization Effects in Fiber Raman and Brillouin Lasers,” IEEE J. Quantum Electron. 15(10), 1157–1160 (1979).
    [CrossRef]
  8. K. Shiraki, M. Ohashi, and M. Tateda, “Performance of strain-free stimulated Brillouin scattering suppression fiber,” J. Lightwave Technol. 14(4), 549–554 (1996).
    [CrossRef]
  9. M. Ohashi and M. Tateda, “Design of strain-free-fiber with nonuniform dopant concentration for stimulated Brillouin scattering suppression,” J. Lightwave Technol. 11(12), 1941–1945 (1993).
    [CrossRef]
  10. R. Rice, M. Wickham, H. Komine, P. Livingston, P. Thielen, and C. Asman, “Optical fiber amplifier and methods of making the same,” US Patent Application US2010/0238538 A1 (September 23, 2010).
  11. A. Yablon, “Multi-wavelength optical fiber refractive index profiling by spatially resolved Fourier transform spectroscopy,” J. Lightwave Technol. 28(4), 360–364 (2010).
    [CrossRef]
  12. R. Tkach, A. Chraplyvy, and R. Derosier, “Spontaneous Brillouin scattering for single-mode fiber characterization,” Electron. Lett. 22(19), 1011–1013 (1986).
    [CrossRef]
  13. P. Dragic, “Estimating the effect of Ge doping on the acoustic damping coefficient via a highly Ge-doped MCVD silica fiber,” J. Opt. Soc. Am. B 26(8), 1614–1620 (2009).
    [CrossRef]
  14. B. Ward and J. Spring, “Finite element analysis of Brillouin gain in SBS-suppressing optical fibers with non-uniform acoustic velocity profiles,” Opt. Express 17(18), 15685–15699 (2009).
    [CrossRef] [PubMed]
  15. E. Dianov and V. Mashinsky, “Germania-based core optical fibers,” J. Lightwave Technol. 23(11), 3500–3508 (2005).
    [CrossRef]
  16. K. Oh and U. Paek, Silica Optical Fiber Technology for Devices and Components (Wiley & Sons, New York, 2012).
  17. E. Bochove and S. Shakir, “Analysis of a spatial-filtering passive fiber laser beam combining system,” IEEE J. Sel. Top. Quantum Electron. 15(2), 320–327 (2009).
    [CrossRef]
  18. D. Marcuse and R. Derosier, “Mode conversion caused by diameter changes of a round dielectric waveguide,” Bell Syst. Tech. J. 48, 3217–3232 (1969).
  19. G. E. Town and J. T. Lizier, “Tapered holey fibers for spot-size and numerical-aperture conversion,” Opt. Lett. 26(14), 1042–1044 (2001).
    [CrossRef] [PubMed]
  20. T. A. Birks, W. J. Wadsworth, and P. S. Russell, “Supercontinuum generation in tapered fibers,” Opt. Lett. 25(19), 1415–1417 (2000).
    [CrossRef] [PubMed]
  21. N. G. Broderick, “Method for pulse transformations using dispersion varying optical fibre tapers,” Opt. Express 18(23), 24060–24069 (2010).
    [CrossRef] [PubMed]
  22. C. Giles, “Lightwave applications of fiber Bragg gratings,” J. Lightwave Technol. 15(8), 1391–1404 (1997).
    [CrossRef]
  23. K. O. Hill, F. Bilodeau, B. Malo, T. Kitagawa, S. Thériault, D. C. Johnson, J. Albert, and K. Takiguchi, “Chirped in-fiber Bragg gratings for compensation of optical-fiber dispersion,” Opt. Lett. 19(17), 1314–1316 (1994).
    [CrossRef] [PubMed]

2010

2009

2005

2001

2000

1999

1997

C. Giles, “Lightwave applications of fiber Bragg gratings,” J. Lightwave Technol. 15(8), 1391–1404 (1997).
[CrossRef]

1996

K. Shiraki, M. Ohashi, and M. Tateda, “Performance of strain-free stimulated Brillouin scattering suppression fiber,” J. Lightwave Technol. 14(4), 549–554 (1996).
[CrossRef]

1994

1993

M. Ohashi and M. Tateda, “Design of strain-free-fiber with nonuniform dopant concentration for stimulated Brillouin scattering suppression,” J. Lightwave Technol. 11(12), 1941–1945 (1993).
[CrossRef]

1991

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

N. Yoshizawa, T. Horiguchi, and T. Kurashima, “Proposal for stimulated Brillouin-scattering suppression by fiber cabling,” Electron. Lett. 27(12), 1100–1101 (1991).
[CrossRef]

1986

R. Tkach, A. Chraplyvy, and R. Derosier, “Spontaneous Brillouin scattering for single-mode fiber characterization,” Electron. Lett. 22(19), 1011–1013 (1986).
[CrossRef]

1979

R. Stolen, “Polarization Effects in Fiber Raman and Brillouin Lasers,” IEEE J. Quantum Electron. 15(10), 1157–1160 (1979).
[CrossRef]

1969

D. Marcuse and R. Derosier, “Mode conversion caused by diameter changes of a round dielectric waveguide,” Bell Syst. Tech. J. 48, 3217–3232 (1969).

Albert, J.

Andrekson, P.

Bilodeau, F.

Birks, T. A.

Bochove, E.

E. Bochove and S. Shakir, “Analysis of a spatial-filtering passive fiber laser beam combining system,” IEEE J. Sel. Top. Quantum Electron. 15(2), 320–327 (2009).
[CrossRef]

Bogatyrev, V.

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

Boggio, J.

Broderick, N. G.

Bubnov, M.

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

Chernikov, S.

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

Chraplyvy, A.

R. Tkach, A. Chraplyvy, and R. Derosier, “Spontaneous Brillouin scattering for single-mode fiber characterization,” Electron. Lett. 22(19), 1011–1013 (1986).
[CrossRef]

Derosier, R.

R. Tkach, A. Chraplyvy, and R. Derosier, “Spontaneous Brillouin scattering for single-mode fiber characterization,” Electron. Lett. 22(19), 1011–1013 (1986).
[CrossRef]

D. Marcuse and R. Derosier, “Mode conversion caused by diameter changes of a round dielectric waveguide,” Bell Syst. Tech. J. 48, 3217–3232 (1969).

Devyatykh, G.

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

Dianov, E.

E. Dianov and V. Mashinsky, “Germania-based core optical fibers,” J. Lightwave Technol. 23(11), 3500–3508 (2005).
[CrossRef]

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

Dragic, P.

Dross, F.

Fragnito, F.

Giles, C.

C. Giles, “Lightwave applications of fiber Bragg gratings,” J. Lightwave Technol. 15(8), 1391–1404 (1997).
[CrossRef]

Gur'yanov, A.

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

Hansryd, J.

Hill, K. O.

Horiguchi, T.

K. Nakajima, M. Ohashi, K. Shiraki, T. Horiguchi, K. Kurokawa, and Y. Miyajima, “Four-wave mixing suppression effect of dispersion distributed fibers,” J. Lightwave Technol. 17(10), 1814–1822 (1999).
[CrossRef]

N. Yoshizawa, T. Horiguchi, and T. Kurashima, “Proposal for stimulated Brillouin-scattering suppression by fiber cabling,” Electron. Lett. 27(12), 1100–1101 (1991).
[CrossRef]

Johnson, D. C.

Kitagawa, T.

Knudsen, S.

Kurashima, T.

N. Yoshizawa, T. Horiguchi, and T. Kurashima, “Proposal for stimulated Brillouin-scattering suppression by fiber cabling,” Electron. Lett. 27(12), 1100–1101 (1991).
[CrossRef]

Kurkov, A.

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

Kurokawa, K.

Li, M.

Li, S.

Lizier, J. T.

Malo, B.

Mamyshev, P.

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

Marconi, J.

Marcuse, D.

D. Marcuse and R. Derosier, “Mode conversion caused by diameter changes of a round dielectric waveguide,” Bell Syst. Tech. J. 48, 3217–3232 (1969).

Mashinsky, V.

Miroshnichenko, S.

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

Miyajima, Y.

Nakajima, K.

Nolan, D.

Ohashi, M.

K. Nakajima, M. Ohashi, K. Shiraki, T. Horiguchi, K. Kurokawa, and Y. Miyajima, “Four-wave mixing suppression effect of dispersion distributed fibers,” J. Lightwave Technol. 17(10), 1814–1822 (1999).
[CrossRef]

K. Shiraki, M. Ohashi, and M. Tateda, “Performance of strain-free stimulated Brillouin scattering suppression fiber,” J. Lightwave Technol. 14(4), 549–554 (1996).
[CrossRef]

M. Ohashi and M. Tateda, “Design of strain-free-fiber with nonuniform dopant concentration for stimulated Brillouin scattering suppression,” J. Lightwave Technol. 11(12), 1941–1945 (1993).
[CrossRef]

Prokhorov, A.

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

Rumyantsev, S.

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

Russell, P. S.

Semenov, S.

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

Semenov, V.

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

Shakir, S.

E. Bochove and S. Shakir, “Analysis of a spatial-filtering passive fiber laser beam combining system,” IEEE J. Sel. Top. Quantum Electron. 15(2), 320–327 (2009).
[CrossRef]

Shiraki, K.

K. Nakajima, M. Ohashi, K. Shiraki, T. Horiguchi, K. Kurokawa, and Y. Miyajima, “Four-wave mixing suppression effect of dispersion distributed fibers,” J. Lightwave Technol. 17(10), 1814–1822 (1999).
[CrossRef]

K. Shiraki, M. Ohashi, and M. Tateda, “Performance of strain-free stimulated Brillouin scattering suppression fiber,” J. Lightwave Technol. 14(4), 549–554 (1996).
[CrossRef]

Spring, J.

Stolen, R.

R. Stolen, “Polarization Effects in Fiber Raman and Brillouin Lasers,” IEEE J. Quantum Electron. 15(10), 1157–1160 (1979).
[CrossRef]

Sysoliatin, A.

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

Takiguchi, K.

Tateda, M.

K. Shiraki, M. Ohashi, and M. Tateda, “Performance of strain-free stimulated Brillouin scattering suppression fiber,” J. Lightwave Technol. 14(4), 549–554 (1996).
[CrossRef]

M. Ohashi and M. Tateda, “Design of strain-free-fiber with nonuniform dopant concentration for stimulated Brillouin scattering suppression,” J. Lightwave Technol. 11(12), 1941–1945 (1993).
[CrossRef]

Thériault, S.

Tkach, R.

R. Tkach, A. Chraplyvy, and R. Derosier, “Spontaneous Brillouin scattering for single-mode fiber characterization,” Electron. Lett. 22(19), 1011–1013 (1986).
[CrossRef]

Town, G. E.

Wadsworth, W. J.

Ward, B.

Westlund, M.

Yablon, A.

Yoshizawa, N.

N. Yoshizawa, T. Horiguchi, and T. Kurashima, “Proposal for stimulated Brillouin-scattering suppression by fiber cabling,” Electron. Lett. 27(12), 1100–1101 (1991).
[CrossRef]

Bell Syst. Tech. J.

D. Marcuse and R. Derosier, “Mode conversion caused by diameter changes of a round dielectric waveguide,” Bell Syst. Tech. J. 48, 3217–3232 (1969).

Electron. Lett.

N. Yoshizawa, T. Horiguchi, and T. Kurashima, “Proposal for stimulated Brillouin-scattering suppression by fiber cabling,” Electron. Lett. 27(12), 1100–1101 (1991).
[CrossRef]

R. Tkach, A. Chraplyvy, and R. Derosier, “Spontaneous Brillouin scattering for single-mode fiber characterization,” Electron. Lett. 22(19), 1011–1013 (1986).
[CrossRef]

IEEE J. Quantum Electron.

R. Stolen, “Polarization Effects in Fiber Raman and Brillouin Lasers,” IEEE J. Quantum Electron. 15(10), 1157–1160 (1979).
[CrossRef]

IEEE J. Sel. Top. Quantum Electron.

E. Bochove and S. Shakir, “Analysis of a spatial-filtering passive fiber laser beam combining system,” IEEE J. Sel. Top. Quantum Electron. 15(2), 320–327 (2009).
[CrossRef]

J. Lightwave Technol.

V. Bogatyrev, M. Bubnov, E. Dianov, A. Kurkov, P. Mamyshev, A. Prokhorov, S. Rumyantsev, V. Semenov, S. Semenov, A. Sysoliatin, S. Chernikov, A. Gur'yanov, G. Devyatykh, and S. Miroshnichenko, “A single-mode fiber with chromatic dispersion varying along the length,” J. Lightwave Technol. 9(5), 561–566 (1991).
[CrossRef]

K. Shiraki, M. Ohashi, and M. Tateda, “Performance of strain-free stimulated Brillouin scattering suppression fiber,” J. Lightwave Technol. 14(4), 549–554 (1996).
[CrossRef]

M. Ohashi and M. Tateda, “Design of strain-free-fiber with nonuniform dopant concentration for stimulated Brillouin scattering suppression,” J. Lightwave Technol. 11(12), 1941–1945 (1993).
[CrossRef]

C. Giles, “Lightwave applications of fiber Bragg gratings,” J. Lightwave Technol. 15(8), 1391–1404 (1997).
[CrossRef]

K. Nakajima, M. Ohashi, K. Shiraki, T. Horiguchi, K. Kurokawa, and Y. Miyajima, “Four-wave mixing suppression effect of dispersion distributed fibers,” J. Lightwave Technol. 17(10), 1814–1822 (1999).
[CrossRef]

J. Hansryd, F. Dross, M. Westlund, P. Andrekson, and S. Knudsen, “Increase of the SBS threshold in a short highly nonlinear fiber by applying a temperature distribution,” J. Lightwave Technol. 19(11), 1691–1697 (2001).
[CrossRef]

E. Dianov and V. Mashinsky, “Germania-based core optical fibers,” J. Lightwave Technol. 23(11), 3500–3508 (2005).
[CrossRef]

M. Li, S. Li, and D. Nolan, “Nonlinear fibers for signal processing using optical Kerr effects,” J. Lightwave Technol. 23(11), 3606–3614 (2005).
[CrossRef]

J. Boggio, J. Marconi, and F. Fragnito, “Experimental and numerical investigation of the SBS-threshold increase in an optical fiber by applying strain distributions,” J. Lightwave Technol. 23(11), 3808–3814 (2005).
[CrossRef]

A. Yablon, “Multi-wavelength optical fiber refractive index profiling by spatially resolved Fourier transform spectroscopy,” J. Lightwave Technol. 28(4), 360–364 (2010).
[CrossRef]

J. Opt. Soc. Am. B

Opt. Express

Opt. Lett.

Other

R. Rice, M. Wickham, H. Komine, P. Livingston, P. Thielen, and C. Asman, “Optical fiber amplifier and methods of making the same,” US Patent Application US2010/0238538 A1 (September 23, 2010).

K. Oh and U. Paek, Silica Optical Fiber Technology for Devices and Components (Wiley & Sons, New York, 2012).

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Figures (5)

Fig. 1
Fig. 1

Idealized representation of the process employed. (a) Conventional GeO2-doped SiO2 preform fabricated with specific radial refractive index profile using a chemical vapor deposition process; (b) a rod is core-drilled out through the side of the preform such that radial gradient of the preform becomes a longitudinal gradient in the rod; (c) rod from (b) is sleeved into a lower refractive index inner cladding tube such that an index-guiding core/clad geometry is achieved; (d) preform from (c) is drawn into fiber such that longitudinal refractive index profile is now present in the optical fiber. Also shown in (d) are the idealized longitudinal refractive index and compositional profiles of the fiber; which are correlated and are defined by the initial radial profile of the preform in (a). The vertical green dotted lines in (d) are guides to the eye.

Fig. 2
Fig. 2

Refractive index profile of the as-made MCVD preform at the position where the core slug was side-drilled out (dashed red line) and the average germania [GeO2] concentration in the core measured at a variety of positions along the length of the as-drawn fiber (solid blue line; specific data points shown as diamonds). Note that the germanium content along the length of fiber follows the refractive index of the as-made preform. The circles and arrows denote the corresponding ordinate and abscissa for each curve. Also provided, in the shaded areas, are examples of length-wise GeO2 gradients in the as-drawn fibers of about 0.55 and 0.25 weight % GeO2/meter.

Fig. 3
Fig. 3

Refractive index profiles at 0.3 and 16.9 m positions along a 20 m length of the longitudinally-graded optical fibers. Profiles were taken at a wavelength of 970 nm.

Fig. 4
Fig. 4

Spectral attenuation of the longitudinally-graded optical fiber and the as-made original MCVD preform. The minimum loss of the longitudinally-graded fiber was about 82 dB/km where as for the original preform, the minimum loss was about 23 dB/km.

Fig. 5
Fig. 5

Stimulated Brillouin scattering spectrum of the longitudinally-graded fiber, interrogated from both ends (arbitrarily A and B), and a conventional single mode fiber (Corning SMF-28TM) measured at a wavelength of 1534nm.

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