Tunable Casimir repulsion with three dimensional topological insulators

In this work, we show that switching between repulsive and attractive Casimir forces by means of external tunable parameters could be realized with two topological insulator plates. We find two regimes where a repulsive (attractive) force is found at small (large) distances between the plates, canceling out at a critical distance. We also study the effects of temperature and uniaxial anisotropy in our findings. (Phys. Rev. Lett. 106, 020403 (2011) and arXiv:1102.0455)