Bound state of solution of Dirac-Coulomb problem with spatially   dependent mass
  The bound state solution of Coulomb Potentials in the Dirac equation is calculated for position dependent mass function M(r) within the framework of asymptotic iteration method (AIM). The eigenfunctions are derived in terms of hypergeometric function and function generator equation of AIM. 
Eser Olgar, Hayder M. Dhahir, H. Mutaf
math-ph math.MP