Engineering optical gradient force from coupled surface plasmon polariton modes in nanoscale plasmonic waveguides
Lu Jiahui, Wang Guanghui†,
       

Optical gradient force of symmetric and antisymmetric SPP modes as a function of gap width d for different metal filling ratios with εs = 1. Panels (a) and (b) are for structure A, (c) and (d) for structure B.