Optical solitons in nematic liquid crystals with Kerr and parabolic law nonlinearities

We use modulation theory to analyze the interaction of optical solitons and vortices with a dielectric interface between two regions of nematic liquid crystals. In the analysis we consider the role of nonlocality, anisotropy and nonlinear reorientation and compare modulation theory results with numerical results. Upon interacting with the interface, nematicons undergo transverse distortion but remain stable and eventually return to a steady state, whereas vortices experience an enhanced instability and can break up into bright beams or solitary waves.

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Theoretical investigation of spatial optical solitons in nematic liquid crystals with negative dielectric anisotropy

Acta Physica Sinica ◽

10.7498/aps.63.184207 ◽

2014 ◽

Vol 63 (18) ◽

pp. 184207

Author(s):

Li Yi-Heng ◽

Wang Jing ◽

Hu Wei ◽

Guo Qi

Keyword(s):

Liquid Crystals ◽

Theoretical Investigation ◽

Nematic Liquid Crystals ◽

Optical Solitons ◽

Dielectric Anisotropy ◽

Spatial Optical Solitons

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Beam splitting in chiral nematic liquid crystals

Photonics Letters of Poland ◽

10.4302/plp.v10i4.867 ◽

2018 ◽

Vol 10 (4) ◽

pp. 109

Author(s):

Filip Sala

Keyword(s):

Liquid Crystal ◽

Liquid Crystals ◽

Nematic Liquid Crystal ◽

Soft Matter ◽

Nematic Liquid Crystals ◽

Beam Propagation Method ◽

Beam Propagation ◽

Optical Solitons ◽

Molecular Reorientation ◽

Chiral Nematic

By lunching the beam into the chiral nematic liquid crystals it is possible to achieve a non-diffractive beam similar to a soliton. This effect is caused by the molecular reorientation i.e. nonlinear response of the material forming the areas of higher refractive index. Diffraction is suppressed by the focusing effect. For appropriate launching conditions it is also possible to achieve a beam which splits into two or more separate beams. Such phenomenon is discussed in this article and analyzed theoretical. To model this effect Fully Vectorial Beam Propagation Method coupled with the Frank-Oseen elastic theory is used. Simulations are performed for various input beam powers, widths, polarization angles and launching positions. Full Text: PDF ReferencesG. Assanto and M. A. Karpierz, "Nematicons: self-localised beams in nematic liquid crystals", Liq. Cryst. 36, 1161–1172 (2009) CrossRef G. Assanto, Nematicons: Spatial Optical Solitons in Nematic Liquid Crystals, John Wiley & Sons Inc. Hoboken, New Jersey (2013) DirectLink A. Piccardi, A. Alberucci, U. Bortolozzo, S. Residori, and G. Assanto, "Soliton gating and switching in liquid crystal light valve", Appl. Phys. Lett. 96, 071104 (2010). CrossRef D. Melo, I. Fernandes, F. Moraes, S. Fumeron, and E. Pereira, "Thermal diode made by nematic liquid crystal", Phys. Lett. A 380, 3121 – 3127 (2016). CrossRef U. Laudyn, M. Kwaśny, F. A. Sala, M. A. Karpierz, N. F. Smyth, G. Assanto, "Curved optical solitons subject to transverse acceleration in reorientational soft matter", Sci. Rep. 7, 12385 (2017) CrossRef M. Kwaśny, U. A. Laudyn, F. A. Sala, A. Alberucci, M. A. Karpierz, G. Assanto, "Self-guided beams in low-birefringence nematic liquid crystals", Phys. Rev. A 86, 013824 (2012) CrossRef F. A. Sala, M. M. Sala-Tefelska, "Optical steering of mutual capacitance in a nematic liquid crystal cell", J. Opt. Soc. Am. B. 35, 133-139 (2018) CrossRef U. A. Laudyn, A. Piccardi, M. Kwasny, M. A. Karpierz, G. Assanto, "Thermo-optic soliton routing in nematic liquid crystals", Opt. Lett. 43, 2296-2299 (2018) CrossRef F. A. Sala, M. M. Sala-Tefelska, M. J. Bujok, J. "Influence of temperature diffusion on molecular reorientation in nematic liquid crystals", Nonlinear Opt. Phys. Mater. 27, 1850011 (2018) CrossRef I-C Khoo Liquid crystals John Wiley & Sons, Inc (2007) DirectLink P. G. de Gennes, J. Prost, The Physics of Liquid Crystals, Clarendon Press (1995) DirectLink U. A. Laudyn, P. S. Jung, M. A. Karpierz, G. Assanto, "Quasi two-dimensional astigmatic solitons in soft chiral metastructures", Sci. Rep. 6, 22923 (2016) CrossRef J. Beeckman, A. Madani, P. J. M. Vanbrabant, P. Henneaux, S-P. Gorza, M. Haelterman, "Switching and intrinsic position bistability of soliton beams in chiral nematic liquid crystals", Phys. Rev. A 83, 033832 (2011) CrossRef A. Madani, J. Beeckman, K. Neyts, "An experimental observation of a spatial optical soliton beam and self splitting of beam into two soliton beams in chiral nematic liquid crystal", Opt. Commun. 298–299, 222-226, (2013) CrossRef G. D. Ziogos, E. E. Kriezis, "Modeling light propagation in liquid crystal devices with a 3-D full-vector finite-element beam propagation method", Opt. Quant. Electron 40, 10 (2008) CrossRef F. A. Sala, M. A. Karpierz, "Chiral and nonchiral nematic liquid-crystal reorientation induced by inhomogeneous electric fields", J. Opt. Soc. Am. B 29, 1465-1472 (2012) CrossRef F. A. Sala, M. A. Karpierz, "Modeling of molecular reorientation and beam propagation in chiral and non-chiral nematic liquid crystals", Opt. Express 20, 13923-13938 (2012) CrossRef F. A. Sala, "Design of false color palettes for grayscale reproduction", Displays, 46, 9-15 (2017) CrossRef

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HIGHLY NONLOCAL OPTICAL SOLITONS AND THEIR OBSERVATION IN NEMATIC LIQUID CRYSTALS

International Journal of Modern Physics B ◽

10.1142/s0217979204026263 ◽

2004 ◽

Vol 18 (20n21) ◽

pp. 2819-2828 ◽

Cited By ~ 3

Author(s):

GAETANO ASSANTO ◽

CLAUDIO CONTI ◽

MARCO PECCIANTI

Keyword(s):

Liquid Crystals ◽

General Theory ◽

Nematic Liquid Crystals ◽

Optical Solitons ◽

Spatial Solitons ◽

Specific System ◽

Arbitrary Degree ◽

Self Focusing ◽

Remarkable Agreement

We investigate 2-dimensional spatial optical solitons in media exhibiting a large nonlocal response coupled with a self-focusing nonlinearity. To this extent, with reference to a specific system in undoped nematic liquid crystals, we develop a general theory of spatial solitons in media with an arbitrary degree of nonlocality and carry out experimental observations to validate the model. The remarkable agreement between predictions and data yields evidence of narrow-waist solitons, revealing an important connection between nonparaxiality and nonlocality and emphasizing the role of nonlocality.

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Optical solitons in nematic liquid crystals: model with saturation effects

Nonlinearity ◽

10.1088/1361-6544/aaa2e2 ◽

2018 ◽

Vol 31 (4) ◽

pp. 1535-1559 ◽

Cited By ~ 6

Author(s):

Juan Pablo Borgna ◽

Panayotis Panayotaros ◽

Diego Rial ◽

Constanza Sánchez F de la Vega

Keyword(s):

Liquid Crystals ◽

Nematic Liquid Crystals ◽

Optical Solitons ◽

Saturation Effects

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Spatial routing with light-induced waveguides in uniaxial nematic liquid crystals

Journal of Nonlinear Optical Physics & Materials ◽

10.1142/s0218863514500477 ◽

2014 ◽

Vol 23 (04) ◽

pp. 1450047 ◽

Cited By ~ 6

Author(s):

Filip A. Sala ◽

Mirosław A. Karpierz ◽

Gaetano Assanto

Keyword(s):

Liquid Crystals ◽

Soft Matter ◽

Nematic Liquid Crystals ◽

Optical Solitons ◽

Guided Wave ◽

Optic Axis ◽

Inhomogeneous Distribution ◽

Input Beam ◽

Beam Position ◽

Graded Index

In reorientational soft-matter with uniaxial character, such as nematic liquid crystals (NLCs), self-confined beams into spatial optical solitons are graded-index waveguides subject to birefringent walkoff. We investigate a router to be realized in a planar cell with an inhomogeneous distribution of the optic axis. Based on the input beam position, the proposed demultiplexer can direct the soliton and the copolarized guided-wave signal(s) to various output ports, enhancing the transverse separation of the exit channels and therefore minimizing crosstalk. Both the soliton and the signal(s) maintain their phasefronts normal to launch and exit wavevectors, allowing for excellent coupling into output channels/fibers at the device exit.

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