Ideal Polymer‐LC Composite Structure for Terahertz Phase Shifters

摘要

Abstract An ideal polymer/liquid crystal (LC) composite structure for terahertz phase shifters is proposed, and the fabrication method of the ideal structure using polymerization induced phase separation is reported. The ideal structure consists of four significant factors: i) the polymer structure surrounds LC droplets like polymer dispersed liquid crystals; ii) the size of the LC droplets is on the order of micrometers; iii) the polymer concentration is much lower than LC concentration like polymer‐stabilized liquid crystals; and iv) the nematic director both within and among the LC droplets has the same orientation. Such a structure is fabricated by photopolymerizing a nematic LC doped with 7 wt% mesogenic monomer under a critical temperature slightly lower than the clearing point of the LC mixture. The polymer/LC composite demonstrates both a short decay response time of 80?ms and a phase shift of 30° for terahertz wave at a frequency of 0.4 THz. Additionally, the transmission loss of the composite for the terahertz wave is discussed.