A popular sophomore-level exercise in quantum mechanics, multiply
(re)appearing in physics journals. The essence of the message is
that the one-dimensional Dirac equation (i.e., the two-component
first-order system) is reducible to a single Schroedinger-like
ordinary differential equation of the second order. The latter
linear eigenvalue problem comprises a confluent hypergeometric
family of the well known special cases which are solvable in terms
of Laguerre polynomials.

MR2786841 Hamzavi, M.; Rajabi, A. A.; Hassanabadi, H. Exactly
complete solutions of the Dirac equation with pseudoharmonic
potential including linear plus Coulomb-like tensor potential.
Internat. J. Modern Phys. A 26 (2011), no. 7-8, 1363--1374. 81Qxx