Source: http://aoot.osa.org/oe/abstract.cfm?uri=oe-20-14-15061
Timestamp: 2019-04-21 16:43:54+00:00

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An effectively single-mode all-solid photonic bandgap fiber with large effective area and low bending loss for compact high-power all-fiber lasers is fully investigated. The pitch dependencies of effective area, bending loss, and effectively single-mode operation are discussed numerically and experimentally. The calculation results indicate that an effectively single-mode all-solid photonic bandgap fiber with an effective area of more than 500 μm2 and a bending loss of less than 0.1 dB/m at a bending radius of 10 cm can be realized by choosing optimum fiber parameters. In a fabricated effectively single-mode all-solid photonic bandgap fiber with 48.0 μm core, the effective area of 712 μm2, the effectively single-mode operation, and the bending loss of less than 0.1 dB/m at a bending radius of 10 cm are achieved simultaneously at 1064 nm.
M.-J. Li, X. Chen, A. Liu, S. Gray, J. Wang, D. T. Walton, and L. A. Zenteno, “Effective area limit for large mode area laser fibers,” in Proc. OFC’08 (2008), paper OTuJ2.
J. Limpert, O. Schmidt, J. Rothhardt, F. Röser, T. Schreiber, A. Tünnermann, S. Ermeneux, P. Yvernault, and F. Salin, “Extended single-mode photonic crystal fiber lasers,” Opt. Express 14(7), 2715–2720 (2006).
C. D. Brooks and F. D. Teodoro, “Multimegawatt peak-power, single-transverse-mode operation of a 100 μm core diameter, Yb-doped rodlike photonic crystal fiber amplifier,” Appl. Phys. Lett. 89(11), 111119 (2006).
S. Huang, C. Zhu, C. Liu, X. Ma, C. Swan, and A. Galvanauskas, “Power scaling of CCC fiber based lasers,” in Proc. CLEO/QELS’08 (2008), paper CThGG1.
C. Liu, G. Chang, N. Litchinitser, D. Guertin, N. Jacobsen, K. Tankala, and A. Galvanauskas, “Chirally coupled core fibers at 1550-nm and 1064-nm for effectively single-mode core size scaling,” in Proc. CLEO/QELS’07 (2007), paper CTuBB3.
A. Galvanauskas, M. C. Swan, and C. Liu, “Effectively-single-mode large core passive and active fibers with chirally-coupled-core structures,” in Proc. CLEO/QELS’08 (2008), paper CMB1.
S. Lefrancois, T. S. Sosnowski, C.-H. Liu, A. Galvanauskas, and F. W. Wise, “Energy scaling of mode-locked fiber lasers with chirally-coupled core fiber,” Opt. Express 19(4), 3464–3470 (2011).
S. Février, R. Jamier, J.-M. Blondy, S. L. Semjonov, M. E. Likhachev, M. M. Bubnov, E. M. Dianov, V. F. Khopin, M. Y. Salganskii, and A. N. Guryanov, “Low-loss singlemode large mode area all-silica photonic bandgap fiber,” Opt. Express 14(2), 562–569 (2006).
D. A. Gaponov, S. Février, M. Devautour, P. Roy, M. E. Likhachev, S. S. Aleshkina, M. Y. Salganskii, M. V. Yashkov, and A. N. Guryanov, “Management of the high-order mode content in large (40 microm) core photonic bandgap Bragg fiber laser,” Opt. Lett. 35(13), 2233–2235 (2010).
S. Fevrier, D. A. Gaponov, P. Roy, M. E. Likhachev, E. M. Dianov, M. Y. Salganskii, M. V. Yashkov, A. N. Guryanov, L. Daniault, M. Hanna, F. Druon, and P. Georges, “All-Silica Photonic Bandgap Fiber Oscillators and Amplifiers,” in Proc. OFC’11 (2011), paper OTuC4.
C. Lecaplain, A. Hideur, S. Février, and P. Roy, “Mode-locked Yb-doped Bragg fiber laser,” Opt. Lett. 34(18), 2879–2881 (2009).
O. N. Egorova, S. L. Semjonov, A. F. Kosolapov, A. N. Denisov, A. D. Pryamikov, D. A. Gaponov, A. S. Biriukov, E. M. Dianov, M. Y. Salganskii, V. F. Khopin, M. V. Yashkov, A. N. Gurianov, and D. V. Kuksenkov, “Single-mode all-silica photonic bandgap fiber with 20-microm mode-field diameter,” Opt. Express 16(16), 11735–11740 (2008).
O. N. Egorova, D. A. Gaponov, N. A. Harchenko, A. F. Kosolapov, S. A. Letunov, A. D. Pryamikov, S. L. Semjonov, E. M. Dianov, V. F. Khopin, M. Y. Salganskii, A. N. Guryanov, and D. V. Kuksenkov, “All-Solid Photonic Bandgap Fiber with Large Mode Area and High Order Modes Suppression,” in Proc. CLEO/QELS’08 (2008), paper CTuMM3.
K. Saitoh, T. Murao, L. Rosa, and M. Koshiba, “Effective area limit of large-mode-area solid-core photonic bandgap fibers for fiber laser applications,” Opt. Fiber Technol. 16(6), 409–418 (2010).
M. Kashiwagi, K. Saitoh, K. Takenaga, S. Tanigawa, S. Matsuo, and M. Fujimaki, “Low bending loss and effectively single-mode all-solid photonic bandgap fiber with an effective area of 650 μm2.,” Opt. Lett. 37(8), 1292–1294 (2012).
K. Nagano, S. Kawakami, and S. Nishida, “Change of the refractive index in an optical fiber due to external forces,” Appl. Opt. 17(13), 2080–2085 (1978).
Fig. 1 (a) Schematic cross-sectional view of effectively single-mode AS-PBGF with seven-cell core and five high-index rod rings and (b) calculated leakage losses of effectively single-mode AS-PBGF with different Δs as a function of normalized frequency V for Λ = 12.0 μm calculated by using finite element method.
Fig. 2 Calculated bending losses of the FM and the HOM as a function of bending radius for V = 1.6 (first photonic bandgap), Δ = 2.0%, and λ = 1064 nm: (a) Λ = 10 μm, (b) Λ = 11 μm, and (c) Λ = 12 μm.
Fig. 3 Calculated bending losses of the FM and the HOM as a function of bending radius for V = 4.65 (third photonic bandgap), Δ = 2.0%, and λ = 1064 nm: (a) Λ = 10 μm, (b) Λ = 11 μm, and (c) Λ = 12 μm.
Fig. 4 Calculated effective area of the FM with different Λs as a function of bending radius for V = 1.6, Δ = 2.0%, and λ = 1064 nm.
Fig. 5 Cross-sectional photo of fabricated effectively single-mode AS-PBGF with seven-cell core and five high-index rod rings (Fiber C).
Fig. 6 (a) Measured transmission spectra of effectively single-mode AS-PBGFs with a length of 1 m and (b) measured transmission losses of effectively single-mode AS-PBGFs in the wavelength range from 1000 nm to 1300 nm.
Fig. 8 Measured and calculated effective areas at 1064 nm of the FM for the effectively single-mode AS-PBGFs under effectively single-mode condition.
Fig. 9 Measured and calculated allowable bending radius ranges as a function of the Λ.

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