Regular papers

Spectral switching control of ultrafast pulses in dual core photonic crystal fibre

¹ International Laser Centre, Ilkovicova 3, 841 04 Bratislava, Slovakia
² Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynska Dolina, 842 48, Bratislava, Slovakia
³ Faculty of Electrical Engineering, Czech Technical University in Prague, Technicka 2, 166 27 Prague, Czech Republic
⁴ Institute of Electronic Materials Technology, Wolczynska 133, 01-919 Warsaw, Poland

^* bugar@ilc.sk

Received: 28 November 2012
Revised: 16 May 2013

Abstract

The work presented in this paper is a study of an all-optical narrow-band switch in extended spectral area by dual core photonic crystal fibre expressing nonlinear coupler performance. The investigation is focused on the nonlinear propagation of femtosecond pulses in the near infrared spectral region at up to 50 kW peak power which induces spectral broadening through almost two octaves. The mutual effect of nonlinear spectral transformation and field redistribution between the two fibre cores is analyzed by both theoretical and experimental approaches. The simulation of the nonlinear propagation is based on coupled generalized nonlinear Schrödinger equations. A modified numerical model utilizing split-step Fourier method was adapted for dual core fibres. The complex experimental study was accomplished for various input settings such as polarization, intensity and selective coupling into each core and the selective detection of spectra from each core. The presented work encompasses promising results obtained regarding a spectral intensity switch between the two output channels by input intensity or polarization change in the S-band of optical communication systems.