Complex rotation method for the Dirac Hamiltoniain

Abstract

A modification of the complex rotation method applied to the Dirac Hamiltonian was proposed. The positions and widths of resonance levels of hydrogenlike ions in the presence of the uniform dc electric field was computed. The external dc electric field was less than the critical value for which the multiparticle processes, such as electron-positron pair creation, become significant. The convergence of the results with respect to the maximum value of the angular momentum was examined. The results show that with increasing field strength, the accuracy of the perturbation expansion deteriorates rapidly.