11:00 〜 11:15
▲ [8a-A409-6] Electrically controllable random laser with dye-doped liquid crystals inside the capillary fiber
キーワード：random laser, liquid crystal, capillary fiber
Owing to the intrinsic birefringence of LCs, the characteristic of random lasers (RLs) have attracted considerable attention by infilling the nematics LCs (NLCs) or polymer dispersed LCs (PDLCs), as a scattering materials, inside the glass cell, capillary tube and the hollow core fiber to produce multiple light scattering. Unlike other scattering materials, LCs can be easily modulation through the external signals, like electric filed, magnetic field, stress, temperature and so on. In this work, the alternative characteristics from RL produced by infilling the NLC inside the single core capillary was demonstrated through the applied sinusoidal voltage and analyzed by the applied sinusoidal voltage.
The preparation of dye-doped LCs (DD-LCs) inside the capillary fiber was described following: First, the dye-dope LC mixtures were produced by doping 0.5 wt% of laser dye Pyrromethene 597 (PM597) into 99.5 wt% nematic liquid crystal (E7). Then, we infilled the admixture into the holey holes of a single core capillary by the capillary effect. The produced DD-LCs infilling capillary fiber was clipped between two ITO-glasses and connected to a sinusoidal AC voltage (VAC) with 1 KHz repetition rate to make sure uniform distribution of the electric field inside the cell. In order to generate RL, the produce capillary was side pump by a frequency doubling Q-switched Nd:YAG laser with the central wavelength at 532 nm.
After excitation, the multiple emission spikes on the top of broad emission spectrum that is one characteristic of RL with coherent feedback. As applied voltage VAC increase, the numbers of emission spikes increase because the disordering of LCs alignment increase. In order to quantitatively define the threshold of RLs, the econophysical function, termed a-stable distribution, was used in this work. It is obvious to see that the obtained value of a from DD-LCs in capillary fibre are 1.71 and 1.37 with VAC= 0V and 15 V, respectively. In this work, we demonstrate that the stronger Levey fluctuation was obtained from DD-LCs in capillary fiber as VAC increases.
The preparation of dye-doped LCs (DD-LCs) inside the capillary fiber was described following: First, the dye-dope LC mixtures were produced by doping 0.5 wt% of laser dye Pyrromethene 597 (PM597) into 99.5 wt% nematic liquid crystal (E7). Then, we infilled the admixture into the holey holes of a single core capillary by the capillary effect. The produced DD-LCs infilling capillary fiber was clipped between two ITO-glasses and connected to a sinusoidal AC voltage (VAC) with 1 KHz repetition rate to make sure uniform distribution of the electric field inside the cell. In order to generate RL, the produce capillary was side pump by a frequency doubling Q-switched Nd:YAG laser with the central wavelength at 532 nm.
After excitation, the multiple emission spikes on the top of broad emission spectrum that is one characteristic of RL with coherent feedback. As applied voltage VAC increase, the numbers of emission spikes increase because the disordering of LCs alignment increase. In order to quantitatively define the threshold of RLs, the econophysical function, termed a-stable distribution, was used in this work. It is obvious to see that the obtained value of a from DD-LCs in capillary fibre are 1.71 and 1.37 with VAC= 0V and 15 V, respectively. In this work, we demonstrate that the stronger Levey fluctuation was obtained from DD-LCs in capillary fiber as VAC increases.