A New Design for All-Normal Near Zero Dispersion Photonic Crystal Fiber with Selective Liquid Infiltration for Broadband Supercontinuum Generation at 1.55？μm
A new design of all-normal and near zero flattened dispersion based on all-silica photonic crystal fibers (PCFs) using selectively liquid infiltration technique has been proposed to realize smooth broadband supercontinuum generation (SCG). The investigation gives the details of the effect of different geometrical parameters along with the infiltrating liquids on the dispersion characteristics of the fiber. Numerical investigations establish a dispersion value of ？0.48？ps/nm/km around the wavelength of 1.55？μm. The optimized design has been found to be suitable for SCG around the C band of wavelength with flat broadband wavelength band (375？nm bandwidth) and smooth spectrum with only a meter long of the PCF. The proposed structure also demonstrates good tunable properties that can help correct possible fabrication mismatch towards a better optimization design for various optical communication systems. 1. Introduction Broadband smooth flattened supercontinuum generation (SCG) has been the target for the researchers for its enormous applications in the field of metrology, optical sensing, optical coherence tomography, wavelength conversion, and so forth [1]. Recent developments for mid-infrared (MIR) SC source have been investigated based on nonsilica fibers [2, 3]. Unconventional PCFs based on aperiodic structure have also been investigated [4]. However, achieving flat broadband smooth SC sources for IR applications remains challenging [1]. One of the foremost requirements of generating broadband flattened SCG is to achieve near zero flattened dispersion around a targeted wavelength. Photonic crystal fibers (PCFs) [5, 6], which enjoys some unique properties like wide band single mode operation, great controllability over dispersion properties, and higher nonlinearity, has been the target host for SCG for the last decades [1]. Researchers have worked on designing novel dispersion profiles with variable air-hole diameter in the cladding [7–13] and this design can be further manipulated for SC generation by pumping at the near zero wavelength [9, 14]. However, the realizing technology of complicated structures or PCF having air-holes of different diameters in microstructure cladding remains truly challenging. An alternative route of achieving similar performance is shown to be practicable by filling the air-holes with liquid crystals [15, 16] or by various liquids such as polymers [17], water [18], and ethanol [19]. Tunable photonic band gap (PBG) effect and long-period fiber grating have been successfully realized with liquid-filled PCFs [20]. Theoretical
References
[1]
J. M. Dudley, G. Genty, and S. Coen, “Supercontinuum generation in photonic crystal fiber,” Reviews of Modern Physics, vol. 78, no. 4, pp. 135–184, 2006.
[2]
J. Swiderski, F. Théberge, M. Michalska, P. Mathieu, and D. Vincent, “High average power supercontinuum generation in a fluoroindate fiber,” Laser Physics Letters, vol. 11, pp. 015106–015109, 2014.
[3]
G. Sobon, M. Klimczak, J. Sotor et al., “Infrared supercontinuum generation in soft-glass photonic crystal fibers pumped at 1560？nm,” Optical Materials Express, vol. 4, pp. 7–15, 2014.
[4]
A. di Tommaso, M. de Sario, L. Mescia, and F. Prudenzano, “Numerical analysis of aperiodic photonic crystal fiber structures for supercontinuum generation,” Optical Engineering, vol. 51, pp. 0350031–0350037, 2012.
[5]
J. Broeng, D. Mogilevstev, S. E. Barkou, and A. Bjarklev, “Photonic crystal fibers: a new class of optical waveguides,” Optical Fiber Technology, vol. 5, no. 3, pp. 305–330, 1999.
[6]
P. S. J. Russell, “Photonic-crystal fibers,” Journal of Lightwave Technology, vol. 24, no. 12, pp. 4729–4749, 2006.
[7]
K. Saitoh, N. J. Florous, and M. Koshiba, “Theoretical realization of holey fiber with flat chromatic dispersion and large mode area: an intriguing defected approach,” Optics Letters, vol. 31, no. 1, pp. 26–28, 2006.
[8]
N. Florous, K. Saitoh, and M. Koshiba, “The role of artificial defects for engineering large effective mode area, flat chromatic dispersion, and low leakage losses in photonic crystal fibers: towards high speed reconfigurable transmission platforms,” Optics Express, vol. 14, no. 2, pp. 901–913, 2006.
[9]
K. Saitoh and M. Koshiba, “Highly nonlinear dispersion-flattened photonic crystal fibers for supercontinuum generation in a telecommunication window,” Optics Express, vol. 12, no. 10, pp. 2027–2032, 2004.
[10]
K. Saitoh, M. Koshiba, T. Hasegawa, and E. Sasaoka, “Chromatic dispersion control in photonic crystal fibers: application to ultra-flattened dispersion,” Optics Express, vol. 11, no. 8, pp. 843–852, 2003.
[11]
F. Poletti, V. Finazzi, T. M. Monro, N. G. R. Broderick, V. Tse, and D. J. Richardson, “Inverse design and fabrication tolerances of ultra-flattened dispersion holey fibers,” Optics Express, vol. 13, no. 10, pp. 3728–3736, 2005.
X. Zhao, G. Zhou, L. Shuguang et al., “Photonic crystal fiber for dispersion compensation,” Applied Optics, vol. 47, no. 28, pp. 5190–5196, 2008.
[14]
F. Begum, Y. Namihira, T. Kinjo, and S. Kaijage, “Supercontinuum generation in square photonic crystal fiber with nearly zero ultra-flattened chromatic dispersion and fabrication tolerance analysis,” Optics Communications, vol. 284, no. 4, pp. 965–970, 2011.
[15]
C. Zhang, G. Kai, Z. Wang et al., “Transformation of a transmission mechanism by filling the holes of normal silica-guiding microstructure fibers with nematic liquid crystal,” Optics Letters, vol. 30, no. 18, pp. 2372–2374, 2005.
[16]
T. T. Alkeskjold, J. L？gsgaard, A. Bjarklev et al., “Highly tunable large-core single-mode liquid-crystal photonic bandgap fiber,” Applied Optics, vol. 45, no. 10, pp. 2261–2264, 2006.
[17]
B. J. Eggleton, C. Kerbage, P. S. Westbrook, R. S. Windeler, and A. Hale, “Microstructured optical fiber devices,” Optics Express, vol. 9, no. 13, pp. 698–713, 2001.
[18]
C. Martelli, J. Canning, K. Lyytikainen, and N. Groothoff, “Water-core fresnel fiber,” Optics Express, vol. 13, no. 10, pp. 3890–3895, 2005.
[19]
S. Yiou, P. Delaye, A. Rouvie et al., “Stimulated Raman scattering in an ethanol core microstructured optical fiber,” Optics Express, vol. 13, no. 12, pp. 4786–4791, 2005.
[20]
C.-P. Yu and J.-H. Liou, “Selectively liquid-filled photonic crystal fibers for optical devices,” Optics Express, vol. 17, no. 11, pp. 8729–8734, 2009.
[21]
K. M. Gundu, M. Kolesik, J. V. Moloney, and K. S. Lee, “Ultra-flattened-dispersion selectively liquid-filled photonic crystal fibers,” Optics Express, vol. 14, no. 15, pp. 6870–6878, 2006.
[22]
C. P. Yu, J. H. Liou, S. S. Huang, and H. C. Chang, “Tunable dual-core liquid-filled photonic crystal fibers for dispersion compensation,” Optics Express, vol. 16, no. 7, pp. 4443–4451, 2008.
[23]
L. Xiao, W. Jin, M. S. Demokan, H. L. Ho, Y. L. Hoo, and C. Zhao, “Fabrication of selective injection microstructured optical fibers with a conventional fusion splicer,” Optics Express, vol. 13, no. 22, pp. 9014–9022, 2005.
[24]
A. Witkowska, K. Lai, S. G. Leon-Saval, W. J. Wadsworth, and T. A. Birks, “All-fiber anamorphic core-shape transitions,” Optics Letters, vol. 31, no. 18, pp. 2672–2674, 2006.
[25]
W. H. Reeves, J. C. Knight, P. S. J. Russell, and P. J. Roberts, “Demonstration of ultra-flattened dispersion in photonic crystal fibers,” Optics Express, vol. 10, no. 14, pp. 609–613, 2002.
[26]
E. W. Washburn, “The dynamics of capillary flow,” Physical Review, vol. 17, pp. 273–283, 1921.
[27]
J. H. Liou, S. S. Huang, and C. P. Yu, “Loss-reduced highly birefringent selectively liquid-filled photonic crystal fibers,” Optics Communications, vol. 283, no. 6, pp. 971–974, 2010.
[28]
N. Vukovic, N. Healy, and A. C. Peacock, “Guiding properties of large mode area silicon microstructured fibers: a route to effective single mode operation,” Journal of the Optical Society of America B: Optical Physics, vol. 28, no. 6, pp. 1529–1533, 2011.
[29]
N. Healy, J. R. Sparks, R. R. He, P. J. A. Sazio, J. V. Badding, and A. C. Peacock, “High index contrast semiconductor ARROW and hybrid ARROW fibers,” Optics Express, vol. 19, no. 11, pp. 10979–10985, 2011.
[30]
Y. Miao, B. Liu, K. Zhang, Y. Liu, and H. Zhang, “Temperature tunability of photonic crystal fiber filled with Fe3O4 nanoparticle fluid,” Applied Physics Letters, vol. 98, no. 2, pp. 021103–021105, 2011.
[31]
M.-Y. Zhang, S.-G. Li, Y.-Y. Yao, B. Fu, and L. Zhang, “A dark hollow beam from a selectively liquid-filled photonic crystal fibre,” Chinese Physics B, vol. 19, no. 4, pp. 047103–047106, 2010.
[32]
W. Qian, C.-L. Zhao, J. Kang, X. Dong, Z. Zhang, and S. Jin, “A proposal of a novel polarizer based on a partial liquid-filled hollow-core photonic bandgap fiber,” Optics Communications, vol. 284, no. 19, pp. 4800–4804, 2011.
[33]
G. P. Agrawal, Nonlinear Fiber Optics, Optics and Photonics Series, Academic Press, San Diego, Calif, USA, 4th edition, 2007.
[34]
Q. Lin and G. P. Agrawal, “Raman response function for silica fibers,” Optics Letters, vol. 31, no. 21, pp. 3086–3088, 2006.
[35]
http://www.cargille.com/.
[36]
http://www.ufe.cz/costp11/.
[37]
D. Jackson, “Towards high-power mid-infrared emission from a fibre laser,” Nature Photonics, vol. 6, pp. 423–431, 2012.
[38]
B. T. Kuhlmey, B. J. Eggleton, and D. K. C. Wu, “Fluid-filled solid-core photonic bandgap fibers,” The Journal of Lightwave Technology, vol. 27, pp. 1617–1630, 2009.
