Electrically tunable photonic bandgap guidance in a liquid-crystal-filled photonic crystal fiber

Analytical method for band structure calculation of photonic crystal fibers filled with liquid crystal

“…For example, when NLC molecular are aligned along y-axis, n hi = diag(n o ,n e ,n o ); when they are aligned along x-axis, n hi =diag(n e ,n o ,n o ). The orientation of the NLC molecules can be controlled by appropriate homeotropic anchoring conditions or external electrical field [5,6]. The approximated circular unit cell represents a typical cylindrical coordinate system which is defined by (r,δ) radial and azumithal axes.…”

“…Nematic liquid crystal (NLC) which is anisotropic material with rod-like molecules is a good infiltration candidate due to its thermal and electrical tunability [5]. It has been experimentally demonstrated that the external electrical field controls the orientation and alignment of the NLC molecules, which consequently tunes the spectral position of the bandgaps [6]. The LC filled PCFs (LCPCF) are finding potential applications in sensing and polarization monitoring owing to the thermal and optical properties of LC infiltrations.…”

A polarization maintaining filter based on a liquid-crystal-photonic-bandgap-fiber

“…In particular, among liquid materials, liquid crystals (LCs) are attractive because they exhibit very high thermo-optic and electro-optic effects, leading to the possibility of realizing tunable components [3]. All-in-fiber tunable devices such as spectral filters, switches, polarization controllers and polarimeters have been fabricated by using this technique and their tunability achieved thermally, electrically or optically [3,4,5]. Birefringence tunability has also been demonstrated in highly birefringent PCF filled with LCs [6].…”

Tunable all-in-fiber waveplates based on negative dielectric liquid crystal photonic bandgap fibers

“…An initial index-guiding PCF can be converted to a bandgap-guiding PCF by infiltrating the air holes with Liquid Crystals (LCs), which allow for optical [2], thermal [3,4], and electrical [4][5][6][7] tuning. A continuously tunable birefringence controller with phase shift of 60° by using a dual-frequency Liquid Crystal filled Photonic BandGap (LCPBG) fibers has been proposed [7].…”