\(L^{2}\) series solution of the relativistic Dirac-Morse problem for all energies. (English) Zbl 1161.81338

Alhaidari, A. D.

Phys. Lett., A 326, No. 1-2, 58-69 (2004).

Summary: We obtain analytic solutions for the one-dimensional Dirac equation with the Morse potential as an infinite series of square integrable functions. These solutions are for all energies, the discrete as well as the continuous. The elements of the spinor basis are written in terms of the confluent hypergeometric functions. They are chosen such that the matrix representation of the Dirac-Morse operator for continuous spectrum (i.e., for scattering energies larger than the rest mass) is tridiagonal. Consequently, the wave equation results in a three-term recursion relation for the expansion coefficients of the wavefunction. The solution of this recursion relation is obtained in terms of the continuous dual Hahn orthogonal polynomials. On the other hand, for the discrete spectrum (i.e., for bound states with energies less than the rest mass) the spinor wave functions result in a diagonal matrix representation for the Dirac-Morse Hamiltonian.

MSC:

81Q05	Closed and approximate solutions to the Schrödinger, Dirac, Klein-Gordon and other equations of quantum mechanics
33C90	Applications of hypergeometric functions

Keywords:

Dirac equation; Morse potential; tridiagonal representations; 3-term recursion relations; continuous dual Hahn polynomials; scattering; relativistic spectrum

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