The repulsive and restoring Casimir force between anisotropic single-negative metamaterial slabs is investigated. Both theoretical and numerical calculations demonstrate the influence of the direction-dependent electromagnetic properties of the metamaterial on the Casimir effect. The electromagnetic responses of the metamaterial parallel and perpendicular to the optical axis affect the Casimir force differently. The polarity of the force as well as its relation to the slab separation are discussed. In the particular case of the restoring Casimir force, we show that multiple equilibria of the force can be formed based on the anisotropy of the single-negative metamaterial.

• Received 7 July 2012

DOI:https://doi.org/10.1103/PhysRevA.87.063823