Photonic clusters formed by dielectric microspheres: Numerical simulations

We show through rigorous calculations that small dielectric microspheres can be organized by an incident electromagnetic plane wave into stable geometric configurations, which we call photonic clusters. The long-ranged optical binding force arises from the multiple scattering between the spheres. A photonic cluster can exhibit a multiplicity of distinct geometries, including quasicrystal-like configurations, with exotic dynamics. Linear stability analysis and dynamical simulations show that the equilibrium configurations can correspond with either stable or a type of quasistable states exhibiting periodic particle motion in the presence of frictional dissipation.