Directionally Asymmetric in Orbital Angular Momentum Generation Using Single‐Layer Dielectric Janus Metasurfaces (Advanced Optical Materials 31/2024)

Janus Metasurfaces with Arbitrary Polarization Control The first Janus metasurfaces demonstrate directionally asymmetric orbital angular momentum generation from arbitrary spin. Titania-based meta-atoms enable operation in the visible range, extending beyond prior demonstrations in microwave and mid-infrared regions. Meta-atoms provide local/global rotation and width control, achieving global directional multifunctionality tailored by the Jones matrix. This multifunctionality in a single-layer design surpasses previous approaches based on spatial multiplexing or vertical stacking, expanding its applicability across diverse domains. For further details, see article number 2401335 by Yao-Wei Huang and co-workers.