Persistent current in one-dimensional non-superconducting mesoscopic   rings: effects of single hopping impurity, in-plane electric field and   foreign atoms
  Persistent current in one-dimensional non-superconducting mesoscopic rings threaded by a slowly varying magnetic flux $\phi$ is studied based on the tight-binding model. The behavior of the persistent current is discussed in three aspects: (a) single hopping impurity, (b) in-plane electric field and (c) in presence of some foreign atoms. 
Santanu K. Maiti