Coexistence of ferromagnetism and superconductivity in   CeO$_{0.3}$F$_{0.7}$BiS$_{2}$
  Bulk magnetization, transport and neutron scattering measurements were performed to investigate the electronic and magnetic properties of a polycrystalline sample of the newly discovered ferromagnetic superconductor, CeO$_{0.3}$F$_{0.7}$BiS$_{2}$. Ferromagnetism develops below T$_{FM}$ = 6.54(8) K and superconductivity is found to coexist with the ferromagnetic state below T$_{SC}$ ~ 4.5 K. Inelastic neutron scattering measurements reveal a very weakly dispersive magnetic excitation at 1.8 meV that can be explained by an Ising-like spin Hamiltonian. Under application of an external magnetic field, the direction of the magnetic moment changes from the c-axis to the ab-plane and the 1.8 meV excitation splits into two modes. A possible mechanism for the unusual magnetism and its relation to superconductivity is discussed. 
J. Lee, S. Demura, M. B. Stone, K. Iida, G. Ehlers, C. R. dela Cruz,   M. Matsuda, K. Deguchi, Y. Takano, Y. Mizuguchi, O. M...
cond-mat.supr-con