A design for a photonic syringe with multimode coupled slot waveguides.

A design is proposed that allows non-stationary field distribution with Bragg gratings in multiple slot waveguides. Selective coupling between modes is achieved or suppressed, according to controllable selection rules, based on mode symmetry. By applying such rules, backward pulling radiation pressure - i.e. toward the light source - can be obtained inside the slots. A mode-switching filter is also proposed, which allows the switching between forward and backward direction of radiation pressure. This "light-actuated" syringe could have potential applications for bidirectional particle trapping and manipulation, optofluidics, optomechanics and biotechnology.