Casimir Force in Layered Materials and Control of the Stable Equilibrium

Quantum interactions between nearly touching neutral interfaces lead to a measurable Casimir force, which is often assumed to be attractive. Our comprehensive computational analysis of atomic force microscopy and surface force apparatus measurements of the Casimir force between layered materials in solvents confirms that the Casimir interactions can give rise to a stable equilibrium. Given the excellent agreement with experiments for a range of materials, we extend the formalism to multiple-layer interfaces and investigate the effects of solvent and compositional changes on the Casimir equilibrium. We explain how the Casimir equilibrium can be tuned precisely and show that the scaling of the equilibrium distance with the thickness of the top layer is a controllable, solvent-dependent parameter. These findings have significant implications for the self-assembly of layered materials and design of future quantum entrapment experiments.