Generating complex vectorial optical fields via surface lattice resonances

Vectorial optical fields (VOFs) with extra degrees of freedom hold promise for many photonic applications. However, current methods to generate VOFs are either bulky in size or exhibit limited functionalities. Here, a novel approach to generate VOFs based on the plasmonic surface lattice resonances (SLRs) is demonstrated. By meticulously arranging two-layer circular arrays with opposite handedness, we achieve a high Q-factor of 10³ via just a few particles, despite the general belief that too small array size suppresses the SLRs. This work presents tunable complex VOFs with distinct inhomogeneous spatial polarization distributions, which may enable various applications in integrated and polarization optics.