Peng Kangzhun, Luo Shiqi, Li Zhi-Yuan, Liang Wenyao
Opt Lett. 2025 May 1;50(9):3102-3105. doi: 10.1364/OL.560670.
Chiral optical effects have significant applications in material science and nanophotonics, particularly in chiral material detection and optical sensing. The toroidal dipole resonance, as a unique electromagnetic multipolar mode, has attracted considerable attention for its distinctive response characteristics in optical research. In this work, we propose a folded metamaterial and investigate the interaction between photonic orbital angular momentum and the toroidal dipole resonances in the designed chiral metamaterials. By varying the folded angle of the metamaterial, we analyze the variations in vortical dichroism response and find that the folded angle significantly affects the intensity and contrast of the vortical dichroism effect. By using electromagnetic multipole resonances theory, we verify that the vortical dichroism enhancement is mainly driven by toroidal dipole resonance intensity and confirm chiral toroidal dipole resonances in the orbital angular momentum dimension. This study provides what we believe to be a new pathway for flexible orbital angular momentum manipulation and the development of chiral toroidal dipole optical devices, especially in optical communications and optical holography applications.
手性光学效应在材料科学和纳米光子学中有着重要应用，特别是在手性材料检测和光学传感方面。作为一种独特的电磁多极模式，环形偶极子共振因其在光学研究中独特的响应特性而备受关注。在这项工作中，我们提出了一种折叠超材料，并研究了光子轨道角动量与设计的手性超材料中环形偶极子共振之间的相互作用。通过改变超材料的折叠角度，我们分析了涡旋二向色性响应的变化，发现折叠角度显著影响涡旋二向色性效应的强度和对比度。利用电磁多极共振理论，我们验证了涡旋二向色性增强主要由环形偶极子共振强度驱动，并在轨道角动量维度中确认了手性环形偶极子共振。这项研究为灵活的轨道角动量操纵和手性环形偶极子光学器件的发展提供了一条新途径，特别是在光通信和光学全息应用中。
