Rayleigh-Wood anomaly-driven robust optical pulling forces in 1D periodic lattices

As a direct manifestation of light-matter interactions, optical forces hold profound significance and broad applications in the microscopic world. We systematically investigate electromagnetic scattering phenomena in 1D lattices and their role in optical force generation. Our findings demonstrate that resonant modes within lattice configurations satisfying the Rayleigh-Wood anomaly condition give rise to substantial modulations in optical forces, prominently featuring the counterintuitive emergence of optical pulling force. The emergence of these pulling forces requires well-defined lattice periodicity, while strong structural disorder effectively suppresses resonant modes and their associated anomalous behavior. Remarkably, this phenomenon exhibits exceptional robustness against variations in material composition, dimensional parameters, geometric configurations, and moderate levels of structural disorder, providing critical insights for designing advanced photonic devices with practical manufacturing tolerances.