Compact dual-core liquid crystal photonic crystal fiber polarization splitter for terahertz applications

Compact terahertz dual core photonic crystal fiber (THz-DC-PCF) polarization splitter is presented and analyzed. The dual core is infiltrated with a nematic liquid crystal (NLC) of type E7 that produces high birefringence between the two polarized modes. The suggested design has a TOPAS as a background material with low material loss. The effect of the structure geometrical parameters is investigated to achieve compact polarization splitter. In addition, the impact of the temperature dependence of the NLC in the THz range on the performance of the suggested splitter is also studied. The numerical results show that the THz-DC-PCF has a device length of 3.848 cm with a low crosstalk of -62 dB for the x- and y-polarized modes. Further, large bandwidth of 58 GHz is achieved around the central frequency of 0.6 THz where the crosstalk is better than -10 dB with a good fabrication tolerance. Therefore, the design is less sensitive to the perturbation introduced during the fabrication process with a strong potential for THz applications.