DEPENDENCE ON PUMP POWER AND CELL THICKNESS OF THE ANCHORING BREAKING TIME IN DYE-DOPED NEMATIC LIQUID CRYSTALS

作者：Palarie Ion^*; Varut Marius Ciprian; Dascalu Constanta; Cimpoiasu Vily Marius

来源：Polytechnical University of Bucharest Scientific Bulletin Series A- Applied Mathematics and Physics, 2018, 80(3): 191-198.

• nematic liquid crystal
• photoalignment
• anchoring breaking time
• cell thickness

We present a study on director reorientation and anchoring breaking time in a pump-probe experiment for dye-doped nematic liquid crystal cells with different pump power and cell thickness. The liquid crystal (LC) used was 4'-n-pentyl-4-cyanobiphenyl (5CB) doped with the dye methyl red (MR). An Ar+ laser beam were used to irradiate the liquid crystal cells with a parallel beam and the twisted nematic structure was investigated with a He-Ne laser beam. We considered LC cells with thickness equal to 8, 12 and 23 mu m filled with 5CB doped with 2% MR. The results had shown that the nematic director is rotated only after a certain time interval, from the moment when the irradiation started. This time is named anchoring breaking time and it decrease as the intensity of the pump power was increased. A linear dependence between the anchoring breaking time and inverse of the pump power was observed for different cell thickness.

• 出版日期2018