Abstract
The behaviors of lateral and normal optical forces between coupled photonic crystal slabs are analyzed. We show that the optical force is periodic with displacement, resulting in stable and unstable equilibrium positions. Moreover, the forces are strongly enhanced by guided resonances of the coupled slabs. Such enhancement is particularly prominent near dark states of the system, and the enhancement effect is strongly dependent on the types of guided resonances involved. These structures lead to enhancement of light-induced pressure over larger areas, in a configuration that is directly accessible to externally incident, free-space optical beams.
Highlights
There has been significant interest in using optical forces for applications such as manipulating nanoscale systems, optical cooling of mechanical motion of mesosopic objects, and demonstrating novel nonlinear optical effects [1,2,3,4,5,6,7,8,9,10,11]
We show that the optical force is periodic with displacement, resulting in stable and unstable equilibrium positions
Small deviations from either of these conditions lead to states with very high quality factors, and with such quality factors strongly dependent upon mechanical displacements. (We will refer to such states that are linked to the dark states as “near-dark states” below.) As a result, the presence of dark states in two-slab systems has important implications for the optical force between them
Summary
There has been significant interest in using optical forces for applications such as manipulating nanoscale systems, optical cooling of mechanical motion of mesosopic objects, and demonstrating novel nonlinear optical effects [1,2,3,4,5,6,7,8,9,10,11]. Near the frequencies of guided resonances, we see significant enhancement of the optical forces In these systems, the presence of in-plane periodic index contrast enables phase-matched coupling between externally incident planewaves and guided modes that are supported by the slab, leading to strong resonant behaviors of individual slabs [12, 13]. The presence of in-plane periodic index contrast enables phase-matched coupling between externally incident planewaves and guided modes that are supported by the slab, leading to strong resonant behaviors of individual slabs [12, 13] The interaction between these resonances in two slabs (Fig. 1) leads to a rich set of effects and opportunities for optical force enhancement.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
