论文标题
使用涡流束对液晶拉曼散射的手性和螺旋贡献
Discrimination of Chiral and Helical Contributions to Raman Scattering of Liquid Crystals using Vortex Beams
论文作者
论文摘要
我们使用具有轨道和旋转角动量的涡流光子场来探测液晶内手性波动。在虹彩的状态下，手性的音高长度明确，我们发现低能拉曼散射可以根据散射矢量和入射光子场的拓扑电荷分解为螺旋和手性成分。基于对异常分散的观察，我们将准弹性散射归因于角动量的转移到旋子样粒子。后者是由于短期排斥和远程偶极相互作用的竞争。我们使用轨道角动量转移的方法为手性和光学主动设备和材料的高级表征开辟了途径。
We use vortex photon fields with orbital and spin angular momentum to probe chiral fluctuations within liquid crystals. In the regime of iridescence with a well-defined pitch length of chirality, we find low energy Raman scattering that can be decomposed into helical and chiral components depending on the scattering vector and the topological charge of the incident photon field. Based on the observation of an anomalous dispersion we attribute quasi-elastic scattering to a transfer of angular momenta to roton-like quasiparticles. The latter are due to a competition of short-range repulsive and long-range dipolar interactions. Our approach using a transfer of orbital angular momentum opens up an avenue for the advanced characterization of chiral and optically active devices and materials.
