Electron in higher-dimensional weakly charged rotating black hole   spacetimes
  We demonstrate separability of the Dirac equation in weakly charged rotating black hole spacetimes in all dimensions. The electromagnetic field of the black hole is described by a test field approximation, with vector potential proportional to the primary Killing vector field. It is shown that the demonstrated separability can be intrinsically characterized by the existence of a complete set of mutually commuting first order symmetry operators generated from the principal Killing-Yano tensor. The presented results generalize the results on integrability of charged particle motion and separability of charged scalar field studied in [1]. 
Marco Cariglia, Valeri P. Frolov, Pavel Krtous, David Kubiznak
gr-qc hep-th