1School of Physics, Peking University, Beijing 100871 2Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080 3Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000 4Department of Physics, Anhui University, Hefei 230039
The Dirac equation for the special case of a spinor in the relativistic potential with the even and odd components related by a constraint is solved exactly when the even component is chosen to be the Hulthén potential. The corresponding radial wavefunctions for two-component spinor are obtained in terms of the hypergeometric function, and the energy spectrum of the bound states is obtained as a solution to a given equation by boundary constraints, in which the nonrelativistic limit reproduces the usual Hulthén potential.