Marshall Kenneth L, Kafka Kyle R P, Urban Nathaniel D, Wallace Jason U, Demos Stavros G
Laboratory for Laser Energetics, University of Rochester, Rochester, NY, USA.
Department of Chemistry, D'Youville College, Buffalo, NY, USA.
Sci Rep. 2022 Jun 29;12(1):10969. doi: 10.1038/s41598-022-14974-5.
Interactions of liquid crystals (LC's) with polarized light have been studied widely and have spawned numerous device applications, including the fabrication of optical elements for high-power and large-aperture laser systems. Currently, little is known about both the effect of incident polarization state on laser-induced-damage threshold (LIDT) and laser-induced functional threshold (LIFT) behavior at sub-LIDT fluences under multipulse irradiation conditions. This work reports on the first study of the nanosecond-pulsed LIDT's dependence on incident polarization for several optical devices employing oriented nematic and chiral-nematic LC's oriented by surface alignment layers. Accelerated lifetime testing was also performed to characterize the ability of these devices to maintain their functional performance under multipulse irradiation as a function of the laser fluence at both 1053 nm and 351 nm. Results show that the LIDT varies as a function of input polarization by 30-80% within the same device, while the multipulse LIFT (which can differ from the nominal LIDT) depends on irradiation conditions such as laser fluence and wavelength.
液晶（LC）与偏振光的相互作用已得到广泛研究，并催生了众多器件应用，包括用于高功率和大孔径激光系统的光学元件制造。目前，对于多脉冲辐照条件下，入射偏振态对激光诱导损伤阈值（LIDT）以及低于LIDT通量时激光诱导功能阈值（LIFT）行为的影响，人们了解甚少。本文报道了首次针对几种采用由表面取向层取向的向列型和手性向列型液晶的光学器件，研究纳秒脉冲LIDT对入射偏振的依赖性。还进行了加速寿命测试，以表征这些器件在多脉冲辐照下，作为1053nm和351nm激光通量函数保持其功能性能的能力。结果表明，在同一器件内，LIDT随输入偏振变化30 - 80%，而多脉冲LIFT（可能与标称LIDT不同）取决于诸如激光通量和波长等辐照条件。
