arXiv:quant-ph/0611288 · Journal of Physics A Mathematical and Theoretical
Comment on ‘Position-dependent effective mass Dirac equations withPT-symmetric and non-PT-symmetric potentials’
Omar Mustafa, S. Habib Mazharimousavi
Abstract
Jia and Dutra ( 2006 J. Phys. A: Math. Gen. 39 11877 ) have considered the one- dimensional non-Hermitian complexified potentials with real spectra in the context of position-dependent mass in the Dirac equation. In their second example, a smooth step shape mass distribution is considered and a non-Hermitian non- PT -symmetric Lorentz vector potential is obtained. They have mapped this problem into an exactly solvable Rosen–Morse Schrödinger model and claimed that the energy spectrum is real. The energy spectrum they have reported is pure imaginary or at best forms an empty set. Their claim on the reality of the energy spectrum is fragile, therefore.