Meng Cuiling, Wu Jin-Sheng, Smalyukh Ivan I
Department of Physics and Chemical Physics Program, University of Colorado, Boulder, CO, USA.
Materials Science and Engineering Program, University of Colorado, Boulder, CO, USA.
Nat Mater. 2023 Jan;22(1):64-72. doi: 10.1038/s41563-022-01414-y. Epub 2022 Dec 1.
Liquid crystals are widely known for their technological uses in displays, electro-optics, photonics and nonlinear optics, but these applications typically rely on defining and switching non-topological spatial patterns of the optical axis. Here, we demonstrate how a liquid crystal's optical axis patterns with singular vortex lines can robustly steer beams of light. External stimuli, including an electric field and light itself, allow us to reconfigure these unusual light-matter interactions. Periodic arrays of vortices obtained by photo-patterning enable the vortex-mediated fission of optical solitons, yielding their lightning-like propagation patterns. Predesigned patterns and spatial trajectories of vortex lines in high-birefringence liquid crystals can steer light into closed loops or even knots. Our vortex lattices might find technological uses in beam steering, telecommunications, virtual reality implementations and anticounterfeiting, as well as possibly offering a model system for probing the interaction of light with defects, including the theoretically predicted, imagination-capturing light-steering action of cosmic strings, elusive defects in cosmology.
液晶因其在显示器、电光、光子学和非线性光学等技术领域的应用而广为人知，但这些应用通常依赖于定义和切换光轴的非拓扑空间模式。在此，我们展示了具有奇异涡旋线的液晶光轴模式如何能够稳健地操控光束。包括电场和光本身在内的外部刺激，使我们能够重新配置这些不同寻常的光与物质的相互作用。通过光图案化获得的涡旋周期性阵列能够实现光学孤子的涡旋介导裂变，产生类似闪电的传播模式。在高双折射液晶中预先设计的涡旋线图案和空间轨迹能够将光引导成闭环甚至纽结。我们的涡旋晶格可能在光束控制、电信、虚拟现实应用和防伪等方面找到技术用途，同时也可能为探究光与缺陷的相互作用提供一个模型系统，其中包括理论上预测的、极具想象力的宇宙弦（宇宙学中难以捉摸的缺陷）的光操控作用。
