The confluent supersymmetry algorithm for Dirac equations with   pseudoscalar potentials
  We introduce the confluent version of the quantum-mechanical supersymmetry (SUSY) formalism for the Dirac equation with a pseudoscalar potential. Application of the formalism to spectral problems is discussed, regularity conditions for the transformed potentials are derived, and normalizability of the transformed solutions is established. Our findings extend and complement former results. 
Alonso Contreras-Astorga and Axel Schulze-Halberg
math-ph hep-th math.MP quant-ph