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Using polymer-dispersed liquid crystals (PDLCs), an electrically switchable binary phase pattern was fabricated to generate Airy beams through a programmable lithographic system. The right main lobe of the reconstructed Airy beam experienced 1.3 mm transverse deflection within 24 cm propagation distance. With a suitable voltage applied, the binary PDLC pattern can be erased due to the index match between polymers and liquid crystals. This versatile approach can be also used to generate other special beams with electrically tunable capability.

Temperature dependent lasing was demonstrated in a dye-doped two-dimensional hexagonal photonic crystal made of holographic polymer-dispersed liquid crystals (LCs) along ΓM direction in TE polarization. A redshift in lasing peaks was observed as the temperature increased from 25 to 45 °C. The downward movement of photonic band of TE polarization, majorly caused by the decrease in the anisotropy of LC droplets with the increase in temperature, is responsible for the redshift in lasing peaks. [ABSTRACT FROM AUTHOR]

Mode-dependent electrically tunable lasing of transverse electric (TE) and transverse magnetic (TM) modes is demonstrated in a dye-doped two-dimensional hexagonal photonic crystal made of holographic polymer-dispersed liquid crystals (LCs). Over 10 nm redshifting in lasing with multiple peaks in nonpolarizing spectra is obtained by applying external voltages up to 40 V. The splitting of lasing spectra between two perpendicular polarizations with the applied voltage is observed, which can be explained through the difference in effective refractive index of LC droplet change with the applied electric field for TE and TM modes. [ABSTRACT FROM AUTHOR]

Lasing actions are demonstrated in two high-symmetry directions (ΓM and ΓK) of a two-dimensional hexagonal photonic crystal from dye-doped holographic polymer-dispersed liquid crystals. The group velocity anomaly, which is peculiar to two-dimensional and three-dimensional photonic crystals, leads to substantial enhancement in local fields in the two-dimensional photonic crystal with a low-index contrast. The difference on the lasing thresholds between the two directions is interpreted as the result of different group velocities of the flat bands where laser oscillation occurred. [ABSTRACT FROM AUTHOR]

A polarization insensitive 2×2 optical switch was fabricated with liquid crystal–polymer composite by means of holography. The highest diffraction efficiency achieved was 85.7%. The rise time and the decay time measured were 36 and 160 μs, respectively, at an applied electric field of 18.2 V/μm. The polarization-dependent loss was 0.03 dB measured for s- and p-polarized light at the wavelength of 632.8 nm. [ABSTRACT FROM AUTHOR]