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Complex time method for quantum dynamics when an exceptional point is encircled in the parameter space

Quantum Physics 2022-07-13 v2 Mathematical Physics math.MP

Abstract

We revisit the complex time method for the application to quantum dynamics as an exceptional point is encircled in the parameter space of the Hamiltonian. The basic idea of the complex time method is using complex contour integration to perform the first-order adiabatic perturbation integral. In this way, the quantum dynamical problem is transformed to a study of singularities in the complex time plane -- transition points -- which represent complex degeneracies of the adiabatic Hamiltonian as the time-dependent parameters defining the encircling contour are analytically continued to complex plane. As an underlying illustration of the approach we discuss a switch between Rabi oscillations and rapid adiabatic passage which occurs upon the encircling of an exceptional point in a special time-symmetric case.

Keywords

Cite

@article{arxiv.2110.14473,
  title  = {Complex time method for quantum dynamics when an exceptional point is encircled in the parameter space},
  author = {Petra Ruth Kapralova-Zdanska},
  journal= {arXiv preprint arXiv:2110.14473},
  year   = {2022}
}

Comments

My paper includes 71 pages and 24 figures out of which 21 pages and 4 figures are Appendixes

R2 v1 2026-06-24T07:14:09.289Z