title: Nontouching nanoparticle diclusters bound by repulsive and attractive Casimir forces.
abstract: We present a scheme for obtaining stable Casimir suspension of dielectric nontouching objects immersed in a fluid, validated here in various geometries consisting of ethanol-separated dielectric spheres and semi-infinite slabs. Stability is induced by the dispersion properties of real dielectric (monolithic) materials. A consequence of this effect is the possibility of stable configurations (clusters) of compact objects, which we illustrate via a molecular two-sphere dicluster geometry consisting of two bound spheres levitated above a gold slab. Our calculations also reveal a strong interplay between material and geometric dispersion, and this is exemplified by the qualitatively different stability behavior observed in planar versus spherical geometries.
authors.affiliation: Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Alejandro W
authors.initials: AW
authors.lastname: Rodriguez
authors.forename: Alexander P
authors.initials: AP
authors.lastname: McCauley
authors.forename: David
authors.initials: D
authors.lastname: Woolf
authors.forename: Federico
authors.initials: F
authors.lastname: Capasso
authors.forename: J D
authors.initials: JD
authors.lastname: Joannopoulos
authors.forename: Steven G
authors.initials: SG
authors.lastname: Johnson