In conventional superconductors inversion symmetry plays an important role in Cooper pair formation. The discovery of superconductors lacking inversion symmetry (non-centrosymmetric) has attracted considerable attention experimentally and theoretically [1-6]. Cooper pairs in conventional superconductors form from two electrons of opposite momentum in the same band at the Fermi energy. The lack of inversion symmetry results in the loss of spin degeneracy and the presence of more than one band at the Fermi surface. This may lead to unconventional superconductivity.