J. R. Salgueiro, Y. S. Kivshar, "Nonlinear plasmonic directional
couplers," Appl. Phys. Lett. 97, 1-3 (2010).

M. Aliramezani, S. M. Nejad, "Numerical analysis and optimization
of a dual-concentric-core photonic crystal fiber for broadband dispersion
compensation," Opt. LaserTech. 42, 1209-1217 (2010).

B. Fu, S. G. Li, Y. Y. Yao, L. Zhang, M. Y. Zhang, "Design of two kinds of dual-core high birefringence and
high coupling degree photonic crystal fibers," Opt.
Commun. 283, 4064-4068 (2010).

A. Martinez, F. Cuesta, J. Marti, "Ultrashort 2-D photonic crystal directional
couplers," IEEE Photon. Technol. Lett. 15, 694-696 (2010).

R. V. J. Raja, K. Porsezian, K. Nithyanandan, "Modulational-instability-induced
supercontinuum generation with saturable nonlinear response," Phys. Rev. A 82, 1-6 (2010).

H. Zhang, S. Chang, J. Yuan, D. Huang, "Supercontinuum generation in chloroform-filled photonic
crystal fiber," Optik 121, 783-787 (2010).

T. Uthayakumar, C. P. Jisha, K. Porsezian, V. C. Kuriakose, "Switching dynamics of a two-dimensional
nonlinear directional coupler in a photopolymer," J.
Opt. 12, 1-8 (2010).

R. V. J. Raja, K. Porsezian, S. K. Varshney, S. Sivabalan, "Modeling photonic crystal fiber
for efficient soliton pulse propagation at 850 nm," Opt.
Commun. 283, 5000-5006 (2010).

R. V. J. Raja, K. Senthilnathan, K. Porsezian, K. Nakkeeran, "Efficient pulse compression
using tapered photonic crystal fiber at 850 nm," IEEE
J. Quantum Electron. 46, 1795-1803 (2010).

A. Kamagate, P. Grelu, P. T. Dinda, J. M. Soto-Crespo, N. Akhmediev, "Stationary and pulsating dissipative light
bullets from a collective variable approach," Phys.
Rev. E 79, 1-11 (2009).

A. Tonello, M. Szpulak, J. Olszewski, S. Wabnitz, A. B. Aceves, W. Urbanczyk, "Nonlinear control of soliton
pulse delay with asymmetric dual-core photonic crystal fibers," Opt. Lett. 34, 920-922 (2009).

J. M. Dudley, J. R. Taylor, "Ten years of nonlinear optics
in photonic crystal fibre," Nat. Photon. 3, 8590 (2009).

J. Li, K. Duan, Y. Wang, X. Cao, Y. Guob, X. Lin, "Design of a single-polarization
single-mode photonic crystal fiber double-core coupler," Optik 120, 490-496 (2009).

K. R. Khan, T. X. Wu, D. N. Christodoulides, G. I. Stegeman, "Soliton switching and multi-frequency generation
in a nonlinear photonic crystal fiber coupler," Opt.
Exp. 16, 9417-9428 (2008).

K. R. Khan, T. X. Wu, "Short pulse propagation in wavelength selective
index-guided photonic crystal fiber coupler," IEEE
J. Sel. Topics Quantum Electron. 14, 752-757 (2008).

B. Kalithasan, K. Nakkeeran, K. Porsezian, P. T. Dinda, N. Mariyappa, "Ultra-short pulse propagation
in birefringent fibers the projection operator method," J.
Opt. A: Pure Appl. Opt. 10, 1-7 (2008).

J. M. Dudley, G. Genty, S. Coen, "Supercontinuum generation in photonic crystal fiber," Rev. Mod. Phys. 78, 1135-1184 (2006).

X. Yu, M. Liu, Y. Chung, M. Yan, P. Shum, "Coupling
coefficient of two-core microstructured optical fiber," Opt.
Commun. 260, 164-169 (2006).

K. P. Hansen, "Introduction to nonlinear photonic
crystal fibers," J. Opt. Fiber Commun. Rep. 2, 226-254 (2005).

K. Nakkeeran, P. K. A. Wai, "Generalized projection operator
method to derive the pulse parameters equations for the nonlinear Schrödinger
equation," Opt. Commun. 244, 377-382 (2005).

I. D. Chremmos, G. Kakarantzas, N. K. Uzunoglu, "Modeling of a highly nonlinear
chalcogenide dual-core photonic crystal fiber coupler," Opt.
Commun. 251, 339-345 (2005).

P. K. A. Wai, K. Nakkeeran, "On the uniqueness of Gaussian
ansatz parameters equations: Generalized projection operator method," Phys. Lett. A 332, 239-243 (2004).

K. Saitoh, M. Koshiba, "Full-vectorial Imaginary-Distance
beam propagation method based on a finite element scheme: Application to photonic
crystal fibers," IEEE J. Quantum Electron. 38, 927-933 (2002).

B. H. Lee, J. B. Eom, J. Kim, D. S. Moon, U. Paek, G. Yang, "Photonic crystal fiber coupler," Opt.
Lett. 27, 812-814 (2002).

A. B. Moubissi, K. Nakkeeran, P. T. Dinda, T. C. Kofane, "Non-lagrangian collective variable
approach for optical solitons in fibres," J.
Phys. A: Math. Gen. 34, 129-136 (2001).

J. N. Kutz, P. Holmes, S. G. Evangelides, J. P. Gordon, "Hamiltonian dynamics of dispersion-managed
breathers," J. Opt. Soc. Am. B 15, 87-96 (1998).

D. Taverner, N. G. R. Broderick, D. J. Richardson, R. I. Laming, M. Ibsen, "Nonlinear self-switching and mulitple gap-soliton
formation in a fiber Bragg grating," Opt. Lett. 23, 328-330 (1998).

S. R. Vigil, Z. Zhou, B. K. Canfield, J. Tostenrude, M. G. Kuzyk, "Dual-core single-mode polymer fiber coupler," J. Opt. Soc. Amer. B 15, 895-900 (1998).

R. Schiek, Y. Baek, G. Krijnen, G. I. Stegeman, I. Baumann, W. Sohler, "All-optical switching in lithium niobate
directional couplers with cascaded nonlinearity," Opt.
Lett. 21, 940-942 (1996).

A. Villeneuve, C. C. Yang, P. G. J. Wigley, G. I. Stegeman, J. S. Aitchison, C. N. lronside, "Ultrafast all-optical switching
in semiconductor nonlinear directional couplers at half the band gap," Appl. Phys. Lett. 61, 147-149 (1992).

R. Boesch, P. Stancioff, C. R. Willis, "Hamiltonian equations for multiple-collective-variable
theories of nonlinear Klein-Gordon equations: A projection-operator approach," Phys. Rev. B 38, 6713-6735 (1988).

D. D. Gusovskii?, E. M. Dianov, A. A. Mai?er, V. B. Neustruev, E. I. Shklovskii?, I. A. Shcherbakov, "Nonlinear light transfer in
tunnel-coupled optical waveguides," Sov. J.
Quantum Electron. 15, 1523 (1985).

D. Anderson, "Variational approach to nonlinear
pulse propagation in optical fibers," Phys.
Rev. A 27, 3135-3145 (1983).

S. M. Jensen, "The nonlinear coherent coupler," IEEE J. Quantum Electron. 18, 1580-1583 (1982).

J. R. Salgueiro, Y. S. Kivshar, "Nonlinear plasmonic directional
couplers," Appl. Phys. Lett. 97, 1-3 (2010).

A. Villeneuve, C. C. Yang, P. G. J. Wigley, G. I. Stegeman, J. S. Aitchison, C. N. lronside, "Ultrafast all-optical switching
in semiconductor nonlinear directional couplers at half the band gap," Appl. Phys. Lett. 61, 147-149 (1992).

R. V. J. Raja, K. Senthilnathan, K. Porsezian, K. Nakkeeran, "Efficient pulse compression
using tapered photonic crystal fiber at 850 nm," IEEE
J. Quantum Electron. 46, 1795-1803 (2010).

K. R. Khan, T. X. Wu, "Short pulse propagation in wavelength selective
index-guided photonic crystal fiber coupler," IEEE
J. Sel. Topics Quantum Electron. 14, 752-757 (2008).

S. M. Jensen, "The nonlinear coherent coupler," IEEE J. Quantum Electron. 18, 1580-1583 (1982).

K. Saitoh, M. Koshiba, "Full-vectorial Imaginary-Distance
beam propagation method based on a finite element scheme: Application to photonic
crystal fibers," IEEE J. Quantum Electron. 38, 927-933 (2002).

A. Martinez, F. Cuesta, J. Marti, "Ultrashort 2-D photonic crystal directional
couplers," IEEE Photon. Technol. Lett. 15, 694-696 (2010).

T. Uthayakumar, C. P. Jisha, K. Porsezian, V. C. Kuriakose, "Switching dynamics of a two-dimensional
nonlinear directional coupler in a photopolymer," J.
Opt. 12, 1-8 (2010).

B. Kalithasan, K. Nakkeeran, K. Porsezian, P. T. Dinda, N. Mariyappa, "Ultra-short pulse propagation
in birefringent fibers the projection operator method," J.
Opt. A: Pure Appl. Opt. 10, 1-7 (2008).

A. B. Moubissi, K. Nakkeeran, P. T. Dinda, T. C. Kofane, "Non-lagrangian collective variable
approach for optical solitons in fibres," J.
Phys. A: Math. Gen. 34, 129-136 (2001).

K. P. Hansen, "Introduction to nonlinear photonic
crystal fibers," J. Opt. Fiber Commun. Rep. 2, 226-254 (2005).

S. R. Vigil, Z. Zhou, B. K. Canfield, J. Tostenrude, M. G. Kuzyk, "Dual-core single-mode polymer fiber coupler," J. Opt. Soc. Amer. B 15, 895-900 (1998).

J. M. Dudley, J. R. Taylor, "Ten years of nonlinear optics
in photonic crystal fibre," Nat. Photon. 3, 8590 (2009).

X. Yu, M. Liu, Y. Chung, M. Yan, P. Shum, "Coupling
coefficient of two-core microstructured optical fiber," Opt.
Commun. 260, 164-169 (2006).

I. D. Chremmos, G. Kakarantzas, N. K. Uzunoglu, "Modeling of a highly nonlinear
chalcogenide dual-core photonic crystal fiber coupler," Opt.
Commun. 251, 339-345 (2005).

B. Fu, S. G. Li, Y. Y. Yao, L. Zhang, M. Y. Zhang, "Design of two kinds of dual-core high birefringence and
high coupling degree photonic crystal fibers," Opt.
Commun. 283, 4064-4068 (2010).

R. V. J. Raja, K. Porsezian, S. K. Varshney, S. Sivabalan, "Modeling photonic crystal fiber
for efficient soliton pulse propagation at 850 nm," Opt.
Commun. 283, 5000-5006 (2010).

K. R. Khan, T. X. Wu, D. N. Christodoulides, G. I. Stegeman, "Soliton switching and multi-frequency generation
in a nonlinear photonic crystal fiber coupler," Opt.
Exp. 16, 9417-9428 (2008).

R. Schiek, Y. Baek, G. Krijnen, G. I. Stegeman, I. Baumann, W. Sohler, "All-optical switching in lithium niobate
directional couplers with cascaded nonlinearity," Opt.
Lett. 21, 940-942 (1996).

B. H. Lee, J. B. Eom, J. Kim, D. S. Moon, U. Paek, G. Yang, "Photonic crystal fiber coupler," Opt.
Lett. 27, 812-814 (2002).

K. Nakkeeran, P. K. A. Wai, "Generalized projection operator
method to derive the pulse parameters equations for the nonlinear Schrödinger
equation," Opt. Commun. 244, 377-382 (2005).

M. Aliramezani, S. M. Nejad, "Numerical analysis and optimization
of a dual-concentric-core photonic crystal fiber for broadband dispersion
compensation," Opt. LaserTech. 42, 1209-1217 (2010).

D. Taverner, N. G. R. Broderick, D. J. Richardson, R. I. Laming, M. Ibsen, "Nonlinear self-switching and mulitple gap-soliton
formation in a fiber Bragg grating," Opt. Lett. 23, 328-330 (1998).

A. Tonello, M. Szpulak, J. Olszewski, S. Wabnitz, A. B. Aceves, W. Urbanczyk, "Nonlinear control of soliton
pulse delay with asymmetric dual-core photonic crystal fibers," Opt. Lett. 34, 920-922 (2009).

H. Zhang, S. Chang, J. Yuan, D. Huang, "Supercontinuum generation in chloroform-filled photonic
crystal fiber," Optik 121, 783-787 (2010).

J. Li, K. Duan, Y. Wang, X. Cao, Y. Guob, X. Lin, "Design of a single-polarization
single-mode photonic crystal fiber double-core coupler," Optik 120, 490-496 (2009).

D. Anderson, "Variational approach to nonlinear
pulse propagation in optical fibers," Phys.
Rev. A 27, 3135-3145 (1983).

A. Kamagate, P. Grelu, P. T. Dinda, J. M. Soto-Crespo, N. Akhmediev, "Stationary and pulsating dissipative light
bullets from a collective variable approach," Phys.
Rev. E 79, 1-11 (2009).

P. K. A. Wai, K. Nakkeeran, "On the uniqueness of Gaussian
ansatz parameters equations: Generalized projection operator method," Phys. Lett. A 332, 239-243 (2004).

R. V. J. Raja, K. Porsezian, K. Nithyanandan, "Modulational-instability-induced
supercontinuum generation with saturable nonlinear response," Phys. Rev. A 82, 1-6 (2010).

R. Boesch, P. Stancioff, C. R. Willis, "Hamiltonian equations for multiple-collective-variable
theories of nonlinear Klein-Gordon equations: A projection-operator approach," Phys. Rev. B 38, 6713-6735 (1988).

J. M. Dudley, G. Genty, S. Coen, "Supercontinuum generation in photonic crystal fiber," Rev. Mod. Phys. 78, 1135-1184 (2006).

D. D. Gusovskii?, E. M. Dianov, A. A. Mai?er, V. B. Neustruev, E. I. Shklovskii?, I. A. Shcherbakov, "Nonlinear light transfer in
tunnel-coupled optical waveguides," Sov. J.
Quantum Electron. 15, 1523 (1985).

G. P. Agrawal, Applications of Nonlinear Fiber
Optics (Academic
Press, 2001).

Comsol
Multiphysics 3.4 (2008) www.comsol.com.