Approximate treatment of the Dirac equation with scalar and vector potentials of rectangular shapes

Abstract

The Dirac equation with scalar potential Us(r) and fourth component of vector po­ tential Uv(r) is considered in the case of the rectangular shapes of these potentials with the same radius R and approximate analytic expressions are derived for the single-particle energy of bound states in certain cases. The results obtained with these expressions are compared with the corresponding "exact" results obtained by solving the eigenvalue equa­ tion numerically.It is found that very good results are obtained for the ground state and for quite a wide range of values of R with one of the proposed expressions. Even the corresponding non-relativistic version of this expession, has not been derived before, to our knowledge.