Casimir-Polder interaction between an atom and a conducting wall in   cosmic string spacetime
  The Casimir-Polder interaction potential is evaluated for a polarizable microparticle and a conducting wall in the geometry of a cosmic string perpendicular to the wall. The general case of the anisotropic polarizability tensor for the microparticle is considered. The corresponding force is a function of the wall-microparticle and cosmic string-microparticle distances. Depending on the orientation of the polarizability tensor principal axes the force can be either attractive or repulsive. The asymptotic behavior of the Casimir-Polder potential is investigated at large and small separations compared to the wavelength of the dominant atomic transitions. We show that the conical defect may be used to control the strength and the sign of the Casimir-Polder force. 
E. R. Bezerra de Mello, V. B. Bezerra, H. F. Mota, A. A. Saharian
hep-th astro-ph.CO cond-mat.mes-hall gr-qc