Fermionic Casimir Effect in Case of Andreev Reflection
  We describe the Fermionic Casimir effect in the case of two spherical superfluid scatterers immersed in a normal Fermi system. It is shown that due to the focusing property of Andreev reflection this new Casimir-like energy is significantly enhanced when compared to the case of normal scatterers with specular reflection. 
Aurel Bulgac, Piotr Magierski and Andreas Wirzba