Design of an ultra-fast all-optical dark soliton switch in a three-core nonlinear directional coupler (TNLDC) made of chalcogenide glasses

摘要

We designed and simulated a three-core nonlinear directional coupler (TNLDC) dark soliton switch. We have optimized the optical properties of chalcogenide glasses such as their high nonlinear refractive index and negative group velocity dispersion and designed a switch having a length of 7 cm and an ultra-fast pulse width of 10 fs with a 100 W power input pulse. The switching characteristic shows that complete switching is possible for different ranges of lengths and pulse widths, and by using the result of the simulation we find a relation between the length and the pulse width with respect to the necessary power for complete dark soliton switching. Also the effect of two photon absorption (2PA) on dark soliton switching was studied and it was shown that 2PA puts some limitations on the switching action but, because of the low value of the 2PA figure of merit for chalcogenide glasses, it did not have any considerable effect on dark soliton switching.