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Light propagation mechanism switching in a liquid crystal infiltrated microstructured polymer optical fibre

Rutkowska K. A., Milenko K., Chojnowska O., Dąbrowski R., Woliński T. R.

Opto-Electronics Review

2015

Vol. 23, No. 4

252-258

In this work studies on propagation properties of a microstructured polymer optical fibre infiltrated with a nematic liquid crystal are presented. Specifically, the influence of an infiltration method on the LC molecular alignment inside fibre air-channels and, thus, on light guidance is discussed. Switching between propagation mechanisms, namely the transition from modified total internal reflection (mTIR) to the photonic bandgap effect obtained by varying external temperature is also demonstrated.

Light-controlled helical pitch and dynamic gratings

Boychuk V. N., Gerus I. I., Iljin A. G., Parka J.

Opto-Electronics Review

2009

Vol. 17, No. 4

287-292

A chiral nematic liquid crystal (LC) with a photo-sensitive chiral agent is employed for a light-controlled modulation of optical activity and used as a model substance for a dynamic diffraction grating recording. The described liquid crystalline system has shown a strong nonlinear response with effective parameter of cubic nonlinearity being much greater of that characteristic of the orientational nonlinearity of LC. A simple mathematical model of light diffraction on the grating of modulated optical activity was developed. Calculated values of intensities and polarisation states of diffracting beams have shown very good agreement with the experimental data. LC systems with light-controlled chirality could be promising media for nonlinear optical applications or all-optical switching devices.

Photonic crystal fibre characterisation with the method of lines

Goncharenko I.A., Marciniak M.

Journal of Telecommunications and Information Technology

2004

nr 1

106-111

Photonic crystal fibres are longitudinally uniform fibres in which in lateral directions periodic refractive index changes occur. Two basically different light guiding mechanisms occur in crystal fibres: index guiding and bandgap guiding. In the paper different modelling methods have been evaluated when applied to photonic crystal fibres. In particular, the method of lines has been shown to be effective and reliable for both classes of photonic crystal fibres. High accuracy results for optical field distribution and dispersion characteristics in a photonic crystal fibre have been achieved with the method of lines.