Collective effects in radiation force on movable quantum dots

Abstract

We theoretically study the resonant radiation force (RF) exerted on interacting quantum dots (QDs). For this purpose, the analytical expression of RF is derived based on the nonlocal theory and the Lorentz force equation. This explicitly shows how RF on QDs behaves under optical excitation of photomediated coupled-states of polaritons in respective QDs confining excitons. In particular, if three QDs are aligned perpendicular to the optical axis, the negative dissipative (scattering and absorbing) force, whose direction is opposite to the light propagation direction, is exerted on the middle QD due to the phase inversion of the induced polarization in it. Furthermore, indirect attractive and repulsive forces arise between QDs at both ends via the middle QD. These effects would enable us to control the spatial dynamics of a QD-assembly by exciting their collective modes.