Abstract

We have studied the recently demonstrated concept of fiber lasers based on active tapered double-clad fiber (T-DCF) in copropagating and counterpropagating configurations, both theoretically and experimentally, and compared the performance to fiber lasers based on conventional cylindrical fibers in end-pumped configurations. Specific properties of T-DCFs were considered theoretically using a rate-equation model developed for tapered fibers, and a detailed comparative study was carried out experimentally. Furthermore, we have studied mode coupling effects in long adiabatic tapers due to coiling and local bending. The results allow us to conclude that, with proper fiber design, the T-DCF technology offers a high-potential alternative for bright, cost-effective fiber devices.

© 2012 Optical Society of America

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    [CrossRef]
  2. V. Filippov, Y. Chamorovskii, J. Kerttula, A. Kholodkov, and O. G. Okhotnikov, “600 W power scalable single transverse mode tapered double-clad fiber laser,” Opt. Express 17, 1203–1214 (2009).
    [CrossRef]
  3. V. Filippov, J. Kerttula, Y. Chamorovskii, K. Golant, and O. G. Okhotnikov, “Highly efficient 750 W tapered double-clad ytterbium fiber laser,” Opt. Express 18, 12499–12512(2010).
    [CrossRef]
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    [CrossRef]
  5. I. Kelson and A. Hardy, “Strongly pumped fiber lasers,” IEEE J. Quantum Electron. 34, 1570–1577 (1998).
    [CrossRef]
  6. V. A. Bagan, S. A. Nikitov, Yu. K. Chamorovskii, and A. D. Shatrov, “Studying the properties of double-clad active cone optic fibers,” J. Commun. Technol. Electron. 55, 1154–1160 (2010).
    [CrossRef]
  7. A. W. Snyder, “Coupling of modes on a tapered dielectric cylinder,” IEEE Trans. Microwave Theory Tech. 18, 383–392 (1970).
    [CrossRef]
  8. D. Marcuse, “Mode conversion in optical fibers with monotonically increasing core radius,” J. Lightwave Technol. 5, 125–133 (1987).
    [CrossRef]
  9. H. Yoda, O. Polynkin, and M. Mansuripur, “Beam quality factor of higher order modes in a step-index fiber,” J. Lightwave Technol. 24, 1350–1355 (2006).
    [CrossRef]
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    [CrossRef]
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    [CrossRef]
  12. A. Fielding, K. Edinger, and C. Davis, “Experimental observation of modal evolution in single-mode tapered optical fibers,” J. Lightwave Technol. 17, 1649–1656 (1999).
    [CrossRef]
  13. P. M. Shankar, L. C. Bobb, and H. D. Krumboltz, “Coupling of modes in bent biconically tapered single-mode fibers,” J. Lightwave Technol. 9, 832–837 (1991).
    [CrossRef]
  14. L. C. Bobb, P. M. Shankar, and H. D. Krumboltz, “Bending effects in biconically tapered single-mode fibers,” J. Lightwave Technol. 8, 1084–1090 (1990).
    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
  26. A. Kosterin, V. Temyanko, M. Fallahi, and M. Mansuripur, “Tapered fiber bundles for combining high-power diode lasers,” Appl. Optics 43, 3893–3900 (2004).
    [CrossRef]
  27. K. M. Golant, “Surface plasma chemical vapor deposition: 20 years of application in glass synthesis for lightguides (a review),” in Proceedings of XXI International Congress on Glass (CD) (2007), paper L13.
  28. J. J. Koponen, M. J. Söderlund, H. J. Hoffman, and S. K. T. Tammela, “Measuring photodarkening from single-mode ytterbium doped silica fibers,” Opt. Express 14, 11539–11544 (2006).
    [CrossRef]
  29. M. E. Fermann, “Single-mode excitation of multimode fibers with ultrashort pulses,” Opt. Lett. 23, 52–54 (1998).
    [CrossRef]

2011

C. Schulze, O. Schmidt, D. Flamm, M. Duparre, and S. Schroter, “Modal analysis of beams emerging from a multi-core fiber using computer-generated holograms,” Proc. SPIE 7914, 79142H1 (2011).
[CrossRef]

A. Iho, A. Tervonen, K. Ylä-Jarkko, S. Tammela, and S. Honkanen, “Characterization of modal coupling of Bragg gratings in large-mode-area fibers,” J. Lightwave Technol. 29, 2031–2038 (2011).
[CrossRef]

2010

V. Filippov, J. Kerttula, Y. Chamorovskii, K. Golant, and O. G. Okhotnikov, “Highly efficient 750 W tapered double-clad ytterbium fiber laser,” Opt. Express 18, 12499–12512(2010).
[CrossRef]

V. A. Bagan, S. A. Nikitov, Yu. K. Chamorovskii, and A. D. Shatrov, “Studying the properties of double-clad active cone optic fibers,” J. Commun. Technol. Electron. 55, 1154–1160 (2010).
[CrossRef]

2009

J. W. Nicholson, A. D. Yablon, J. M Fini, and M. D. Mermelstein, “Measuring the modal content of large-mode-area fibers,” IEEE J. Sel. Top. Quantum Electron. 15, 61–70(2009).
[CrossRef]

V. Filippov, Y. Chamorovskii, J. Kerttula, A. Kholodkov, and O. G. Okhotnikov, “600 W power scalable single transverse mode tapered double-clad fiber laser,” Opt. Express 17, 1203–1214 (2009).
[CrossRef]

2008

2007

2006

2004

1999

1998

M. E. Fermann, “Single-mode excitation of multimode fibers with ultrashort pulses,” Opt. Lett. 23, 52–54 (1998).
[CrossRef]

I. Kelson and A. Hardy, “Strongly pumped fiber lasers,” IEEE J. Quantum Electron. 34, 1570–1577 (1998).
[CrossRef]

1997

1991

L. C. Bobb, H. D. Krumboltz, and P. M. Shankar, “Pressure sensor that uses bent biconically tapered single-mode fibers,” Opt. Lett. 16, 112–114 (1991).
[CrossRef]

P. M. Shankar, L. C. Bobb, and H. D. Krumboltz, “Coupling of modes in bent biconically tapered single-mode fibers,” J. Lightwave Technol. 9, 832–837 (1991).
[CrossRef]

1990

L. C. Bobb, P. M. Shankar, and H. D. Krumboltz, “Bending effects in biconically tapered single-mode fibers,” J. Lightwave Technol. 8, 1084–1090 (1990).
[CrossRef]

1987

D. Marcuse, “Mode conversion in optical fibers with monotonically increasing core radius,” J. Lightwave Technol. 5, 125–133 (1987).
[CrossRef]

1986

1976

T. Ozeki and B. S. Kawasaki, “Mode behaviour in a tapered multimode fibre,” Electron. Lett. 12, 407–408 (1976).
[CrossRef]

1975

1974

1970

A. W. Snyder, “Coupling of modes on a tapered dielectric cylinder,” IEEE Trans. Microwave Theory Tech. 18, 383–392 (1970).
[CrossRef]

Andermahr, N.

N. Andermahr, T. Theeg, and C. Fallnich, “Novel approach for polarization-sensitive measurements of transverse modes in few-mode optical fibers,” Appl. Phys. B 91, 353–357(2008).
[CrossRef]

Baek, S.

Bagan, V. A.

V. A. Bagan, S. A. Nikitov, Yu. K. Chamorovskii, and A. D. Shatrov, “Studying the properties of double-clad active cone optic fibers,” J. Commun. Technol. Electron. 55, 1154–1160 (2010).
[CrossRef]

Bobb, L. C.

P. M. Shankar, L. C. Bobb, and H. D. Krumboltz, “Coupling of modes in bent biconically tapered single-mode fibers,” J. Lightwave Technol. 9, 832–837 (1991).
[CrossRef]

L. C. Bobb, H. D. Krumboltz, and P. M. Shankar, “Pressure sensor that uses bent biconically tapered single-mode fibers,” Opt. Lett. 16, 112–114 (1991).
[CrossRef]

L. C. Bobb, P. M. Shankar, and H. D. Krumboltz, “Bending effects in biconically tapered single-mode fibers,” J. Lightwave Technol. 8, 1084–1090 (1990).
[CrossRef]

Chamorovskii, Y.

Chamorovskii, Yu. K.

V. A. Bagan, S. A. Nikitov, Yu. K. Chamorovskii, and A. D. Shatrov, “Studying the properties of double-clad active cone optic fibers,” J. Commun. Technol. Electron. 55, 1154–1160 (2010).
[CrossRef]

Chernikov, S. V.

Codemard, C.

Davis, C.

Duparre, M.

C. Schulze, O. Schmidt, D. Flamm, M. Duparre, and S. Schroter, “Modal analysis of beams emerging from a multi-core fiber using computer-generated holograms,” Proc. SPIE 7914, 79142H1 (2011).
[CrossRef]

Edinger, K.

Fallahi, M.

A. Kosterin, V. Temyanko, M. Fallahi, and M. Mansuripur, “Tapered fiber bundles for combining high-power diode lasers,” Appl. Optics 43, 3893–3900 (2004).
[CrossRef]

Fallnich, C.

N. Andermahr, T. Theeg, and C. Fallnich, “Novel approach for polarization-sensitive measurements of transverse modes in few-mode optical fibers,” Appl. Phys. B 91, 353–357(2008).
[CrossRef]

Fermann, M. E.

Fielding, A.

Filippov, V.

Fini, J. M

J. W. Nicholson, A. D. Yablon, J. M Fini, and M. D. Mermelstein, “Measuring the modal content of large-mode-area fibers,” IEEE J. Sel. Top. Quantum Electron. 15, 61–70(2009).
[CrossRef]

Flamm, D.

C. Schulze, O. Schmidt, D. Flamm, M. Duparre, and S. Schroter, “Modal analysis of beams emerging from a multi-core fiber using computer-generated holograms,” Proc. SPIE 7914, 79142H1 (2011).
[CrossRef]

Gapontsev, V. P.

Ghalmi, S.

Golant, K.

Golant, K. M.

K. M. Golant, “Surface plasma chemical vapor deposition: 20 years of application in glass synthesis for lightguides (a review),” in Proceedings of XXI International Congress on Glass (CD) (2007), paper L13.

Golowich, S. E.

Hardy, A.

I. Kelson and A. Hardy, “Strongly pumped fiber lasers,” IEEE J. Quantum Electron. 34, 1570–1577 (1998).
[CrossRef]

Hoffman, H. J.

Honkanen, S.

Hudson, M. C.

Iho, A.

Jeong, Y.

Kawasaki, B. S.

T. Ozeki and B. S. Kawasaki, “Mode behaviour in a tapered multimode fibre,” Electron. Lett. 12, 407–408 (1976).
[CrossRef]

Kelson, I.

I. Kelson and A. Hardy, “Strongly pumped fiber lasers,” IEEE J. Quantum Electron. 34, 1570–1577 (1998).
[CrossRef]

Kerttula, J.

Kholodkov, A.

Koponen, J. J.

Kosterin, A.

A. Kosterin, V. Temyanko, M. Fallahi, and M. Mansuripur, “Tapered fiber bundles for combining high-power diode lasers,” Appl. Optics 43, 3893–3900 (2004).
[CrossRef]

Krumboltz, H. D.

L. C. Bobb, H. D. Krumboltz, and P. M. Shankar, “Pressure sensor that uses bent biconically tapered single-mode fibers,” Opt. Lett. 16, 112–114 (1991).
[CrossRef]

P. M. Shankar, L. C. Bobb, and H. D. Krumboltz, “Coupling of modes in bent biconically tapered single-mode fibers,” J. Lightwave Technol. 9, 832–837 (1991).
[CrossRef]

L. C. Bobb, P. M. Shankar, and H. D. Krumboltz, “Bending effects in biconically tapered single-mode fibers,” J. Lightwave Technol. 8, 1084–1090 (1990).
[CrossRef]

Li, Y.-F.

Lit, J. W. Y.

Mansuripur, M.

H. Yoda, O. Polynkin, and M. Mansuripur, “Beam quality factor of higher order modes in a step-index fiber,” J. Lightwave Technol. 24, 1350–1355 (2006).
[CrossRef]

A. Kosterin, V. Temyanko, M. Fallahi, and M. Mansuripur, “Tapered fiber bundles for combining high-power diode lasers,” Appl. Optics 43, 3893–3900 (2004).
[CrossRef]

Marcuse, D.

D. Marcuse, “Mode conversion in optical fibers with monotonically increasing core radius,” J. Lightwave Technol. 5, 125–133 (1987).
[CrossRef]

Mermelstein, M. D.

J. W. Nicholson, A. D. Yablon, J. M Fini, and M. D. Mermelstein, “Measuring the modal content of large-mode-area fibers,” IEEE J. Sel. Top. Quantum Electron. 15, 61–70(2009).
[CrossRef]

Nicholson, J. W.

J. W. Nicholson, A. D. Yablon, J. M Fini, and M. D. Mermelstein, “Measuring the modal content of large-mode-area fibers,” IEEE J. Sel. Top. Quantum Electron. 15, 61–70(2009).
[CrossRef]

J. W. Nicholson, A. D. Yablon, S. Ramachandran, and S. Ghalmi, “Spatially and spectrally resolved imaging of modal content in large-mode-area fibers,” Opt. Express 16, 7233–7243 (2008).
[CrossRef]

Nikitov, S. A.

V. A. Bagan, S. A. Nikitov, Yu. K. Chamorovskii, and A. D. Shatrov, “Studying the properties of double-clad active cone optic fibers,” J. Commun. Technol. Electron. 55, 1154–1160 (2010).
[CrossRef]

Nilsson, J.

Okhotnikov, O. G.

Olshansky, R.

Ozeki, T.

T. Ozeki and B. S. Kawasaki, “Mode behaviour in a tapered multimode fibre,” Electron. Lett. 12, 407–408 (1976).
[CrossRef]

Pessa, M.

Philippov, V.

Polynkin, O.

Ramachandran, S.

Reed, W. A.

Ritger, A. J.

Schmidt, O.

C. Schulze, O. Schmidt, D. Flamm, M. Duparre, and S. Schroter, “Modal analysis of beams emerging from a multi-core fiber using computer-generated holograms,” Proc. SPIE 7914, 79142H1 (2011).
[CrossRef]

Schroter, S.

C. Schulze, O. Schmidt, D. Flamm, M. Duparre, and S. Schroter, “Modal analysis of beams emerging from a multi-core fiber using computer-generated holograms,” Proc. SPIE 7914, 79142H1 (2011).
[CrossRef]

Schulze, C.

C. Schulze, O. Schmidt, D. Flamm, M. Duparre, and S. Schroter, “Modal analysis of beams emerging from a multi-core fiber using computer-generated holograms,” Proc. SPIE 7914, 79142H1 (2011).
[CrossRef]

Shankar, P. M.

L. C. Bobb, H. D. Krumboltz, and P. M. Shankar, “Pressure sensor that uses bent biconically tapered single-mode fibers,” Opt. Lett. 16, 112–114 (1991).
[CrossRef]

P. M. Shankar, L. C. Bobb, and H. D. Krumboltz, “Coupling of modes in bent biconically tapered single-mode fibers,” J. Lightwave Technol. 9, 832–837 (1991).
[CrossRef]

L. C. Bobb, P. M. Shankar, and H. D. Krumboltz, “Bending effects in biconically tapered single-mode fibers,” J. Lightwave Technol. 8, 1084–1090 (1990).
[CrossRef]

Shatrov, A. D.

V. A. Bagan, S. A. Nikitov, Yu. K. Chamorovskii, and A. D. Shatrov, “Studying the properties of double-clad active cone optic fibers,” J. Commun. Technol. Electron. 55, 1154–1160 (2010).
[CrossRef]

Snyder, A. W.

A. W. Snyder, “Coupling of modes on a tapered dielectric cylinder,” IEEE Trans. Microwave Theory Tech. 18, 383–392 (1970).
[CrossRef]

Söderlund, M. J.

Soh, D. B. S.

Tammela, S.

Tammela, S. K. T.

Taylor, J. R.

Temyanko, V.

A. Kosterin, V. Temyanko, M. Fallahi, and M. Mansuripur, “Tapered fiber bundles for combining high-power diode lasers,” Appl. Optics 43, 3893–3900 (2004).
[CrossRef]

Tervonen, A.

Theeg, T.

N. Andermahr, T. Theeg, and C. Fallnich, “Novel approach for polarization-sensitive measurements of transverse modes in few-mode optical fibers,” Appl. Phys. B 91, 353–357(2008).
[CrossRef]

Wielandy, S.

Yablon, A. D.

J. W. Nicholson, A. D. Yablon, J. M Fini, and M. D. Mermelstein, “Measuring the modal content of large-mode-area fibers,” IEEE J. Sel. Top. Quantum Electron. 15, 61–70(2009).
[CrossRef]

J. W. Nicholson, A. D. Yablon, S. Ramachandran, and S. Ghalmi, “Spatially and spectrally resolved imaging of modal content in large-mode-area fibers,” Opt. Express 16, 7233–7243 (2008).
[CrossRef]

Ylä-Jarkko, K.

Yoda, H.

Zhu, Y.

Appl. Opt.

Appl. Optics

A. Kosterin, V. Temyanko, M. Fallahi, and M. Mansuripur, “Tapered fiber bundles for combining high-power diode lasers,” Appl. Optics 43, 3893–3900 (2004).
[CrossRef]

Appl. Phys. B

N. Andermahr, T. Theeg, and C. Fallnich, “Novel approach for polarization-sensitive measurements of transverse modes in few-mode optical fibers,” Appl. Phys. B 91, 353–357(2008).
[CrossRef]

Electron. Lett.

T. Ozeki and B. S. Kawasaki, “Mode behaviour in a tapered multimode fibre,” Electron. Lett. 12, 407–408 (1976).
[CrossRef]

IEEE J. Quantum Electron.

I. Kelson and A. Hardy, “Strongly pumped fiber lasers,” IEEE J. Quantum Electron. 34, 1570–1577 (1998).
[CrossRef]

IEEE J. Sel. Top. Quantum Electron.

J. W. Nicholson, A. D. Yablon, J. M Fini, and M. D. Mermelstein, “Measuring the modal content of large-mode-area fibers,” IEEE J. Sel. Top. Quantum Electron. 15, 61–70(2009).
[CrossRef]

IEEE Trans. Microwave Theory Tech.

A. W. Snyder, “Coupling of modes on a tapered dielectric cylinder,” IEEE Trans. Microwave Theory Tech. 18, 383–392 (1970).
[CrossRef]

J. Commun. Technol. Electron.

V. A. Bagan, S. A. Nikitov, Yu. K. Chamorovskii, and A. D. Shatrov, “Studying the properties of double-clad active cone optic fibers,” J. Commun. Technol. Electron. 55, 1154–1160 (2010).
[CrossRef]

J. Lightwave Technol.

J. Opt. Soc. Am. A

Opt. Express

Opt. Lett.

Proc. SPIE

C. Schulze, O. Schmidt, D. Flamm, M. Duparre, and S. Schroter, “Modal analysis of beams emerging from a multi-core fiber using computer-generated holograms,” Proc. SPIE 7914, 79142H1 (2011).
[CrossRef]

Other

K. M. Golant, “Surface plasma chemical vapor deposition: 20 years of application in glass synthesis for lightguides (a review),” in Proceedings of XXI International Congress on Glass (CD) (2007), paper L13.

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Figures (19)

Fig. 1.
Fig. 1.

(a) Schematic illustration of the simulated laser geometry. For copropagating and counterpropagating configurations, pump direction (0L) coincides, or is opposite, to output beam direction respectively. (b) Energy level system of Yb3+ ions. Parameters are defined in the text.

Fig. 2.
Fig. 2.

Effective concentration of ytterbium ions in a simulated cylindrical fiber representing the T-DCF.

Fig. 3.
Fig. 3.

Longitudinal distributions of (a) pump and (b) signal power for simulated copropagating and counterpropagating laser schemes for 100 W of absorbed pump power. Fiber length for each configuration was selected to yield maximum output power.

Fig. 4.
Fig. 4.

Small-signal inverted population distribution for the different laser configurations calculated for a 25 m fiber length.

Fig. 5.
Fig. 5.

Pump conversion efficiency versus absorbed pump power.

Fig. 6.
Fig. 6.

Intracavity power density distribution for different laser schemes. The numerical values in the legend refer to the average intracavity power density per unit length.

Fig. 7.
Fig. 7.

The ratio of length for cylindrical and tapered fiber with equal volume of active material versus tapering ratio.

Fig. 8.
Fig. 8.

S2-measurement setup for tapered fiber. OSA, optical spectrum analyzer.

Fig. 9.
Fig. 9.

Cladding diameter versus length of the tapered fiber.

Fig. 10.
Fig. 10.

(a) Counterpropagation and (b) copropagation laser schemes.

Fig. 11.
Fig. 11.

(a) Typical output pulse shape and (b) spectrum for self-pulsing operation.

Fig. 12.
Fig. 12.

Output signal spectra of counterpropagation tapered fiber laser for three different values of launched pump power.

Fig. 13.
Fig. 13.

Mode coupling measurement setup.

Fig. 14.
Fig. 14.

(a) Spectrum of light transmitted through the optical system consisting of the taper and the spatial single-mode filter. Taper coil radius is 25 cm, mean deviation is 0.73 dB. (b) Fourier transform of the spectrum presented in (a).

Fig. 15.
Fig. 15.

(a) Spectrum of light propagated through the taper and the spatial filter. Taper coil radius is 15 cm, average signal is 3.38 dB, and deviation is 0.66 dB. (b) Fourier transform of the spectrum shown in (a).

Fig. 16.
Fig. 16.

Local bending of the wide side of the T-DCF with 5 cm radius: (a) Output spectrum with average level of 3.17 dB, deviation is 0.66 dB. (b) Fourier transform of the spectrum in Fig. 16(a).

Fig. 17.
Fig. 17.

Local bending of the narrow section of the T-DCF with 5 cm radius: (a) Output spectrum; the average level is 6.02dB, deviation is 1.61 dB. (b) Fourier transform of the spectrum in Fig. 17(a).

Fig. 18.
Fig. 18.

Far field distribution of the beam from the wide output of the T-DCF, and the near field (upper inset) and far-field (lower inset) two-dimensional images.

Fig. 19.
Fig. 19.

Schematic illustration of the development of self-pulsing in (a) counterpropagating and (b) copropagating configurations.

Tables (1)

Tables Icon

Table 1. Characterization Results for the Studied Laser Schemes

Equations (20)

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

PCE=S·L·C,
{±dS±dz=ΓS·[(σes+σas)·N2σas·N]·S±αs·S±±dP±dz=ΓP·[σap·N(σap+σep)·N2]·P±αp·P±,
{N=N1+N2tN1=1τ1·N1+1τ2·N2+ω21·N2ω12·N1tN2=1τ1·N11τ2·N2ω21·N2+ω12·N1,
N2(z)=N(z)·(Γp·σap·λp·(P++P)+Γs·σas·λs·(S++S))/(Ahcτ+Γp·λp·(σap+σep)·(P++P)+Γs·λs·(σas+σes)·(S++S)),
{P+(0)=P+P(L)=0S+(0)=R1·S(0)S(L)=R2·S+(L),
Ntaper(z)=ΔVtaperΔVcylinder·N0=rtaper2(z)r02·N0,
dPvgntdz=1r2(0)·exp(α·z)·dr2(z)dz.
r2(z)r2(0)r2(L)r2(0)=zL.
dPvgntdz=1L(1r2(L)r2(0))exp(αp·z).
dPpump+dz=dP+dzdPvgntdz.
LcylinderLtaper=13(T2+T+1),
Cnm=0.5n12n22neff,nneff,m1aaz,
Cnm;pqψ=002πεnm(i)εpq(i+1)[J0(βnm(i)ψr)+2jJ1(βnm(i)ψr)·cosφ]rdrdφ,
Cnm,pq=0LCnm,pq1R(z)dz,
I=S·E12ds,
I=i=1Nci2SEi2ds+2i,j=1NcicjEi·S·Ejds·cos(2πΔnijeffLpfc),
τij=ΔnijeffLpc.
LDCF=(D·NA·FDCF2·BPP·T)2,
LT-DCF=(D·NA·FT-DCF2·BPP)2,
LT-DCFLDCF=(FT-DCFFDCFT)2.

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