ABSTRACT

Blue phases (BPs) in chiral nematic liquid crystals (LC) remained a field of ample research interest due to their exotic optical properties. In the present work, we report the doping effect of dimensionality varying NPs (alumina nanowires [ANWs] and citrate buffer stabilized gold nanoparticles [GNPs]) on the phase transition temperatures and stability of the BP temperature range using polarizing optical microscopy. An increase in the BP thermal stability after the dispersion of NP is observed than an undoped sample. Doping of GNPs and ANWs could expand the BP temperature range of ∼8.0°C and ∼4.5°C respectively at an optimum concentration of dopants. A decrease in BP temperature range is noticed beyond a critical concentration of doped NPs. A platelet type texture, which corresponds to BP-I/BP-II is clearly seen.

摘要

手性向列液晶 (LC) 中的蓝相 (BP) 由于其奇异的光学特性而仍然是一个广泛的研究领域。在目前的工作中，我们使用偏振光学显微镜报告了维数变化的 NPs（氧化铝纳米线 [ANWs] 和柠檬酸盐缓冲稳定的金纳米颗粒 [GNPs]）对相变温度和 BP 温度范围稳定性的掺杂影响。与未掺杂的样品相比，观察到 NP 分散后 BP 热稳定性的增加。在最佳掺杂浓度下，GNPs 和 ANWs 的掺杂可以将 BP 温度范围分别扩大到 ~8.0°C 和 ~4.5°C。注意到 BP 温度范围的降低超出了掺杂 NP 的临界浓度。与 BP-I/BP-II 对应的血小板型纹理清晰可见。