The Klein-Gordon Equation of Generalized Hulthen Potential in Complex   Quantum Mechanics
  We have investigated the reality of exact bound states of complex and/or PT-symmetric non-Hermitian exponential-type generalized Hulthen potential. The Klein-Gordon equation has been solved by using the Nikiforov-Uvarov method which is based on solving the second-order linear differential equations by reduction to a generalized equation of hypergeometric type. In many cases of interest, negative and positive energy states have been discussed for different types of complex potentials. 
Mehmet Simsek and Harun Egrifes