English

Open quantum systems decay across time

Quantum Physics 2021-06-02 v1

Abstract

The description of an open quantum system's decay almost always requires several approximations as to remain tractable. Here, we first revisit the meaning, domain and seeming contradictions of a few of the most widely used of such approximations: semi-group Markovianity, linear response theory, Wigner--Weisskopf and rotating-wave approximation. Secondly, we derive an effective time-dependent decay theory and corresponding generalized quantum regression relations for an open quantum system linearly coupled to an environment. This theory covers all timescales, and subsumes the Markovian and linear-response results as limiting cases. Finally, we apply our theory to the phenomenon of quantum friction.

Keywords

Cite

@article{arxiv.2006.02358,
  title  = {Open quantum systems decay across time},
  author = {Juliane Klatt and Chahan Michael Kropf and Stefan Yoshi Buhmann},
  journal= {arXiv preprint arXiv:2006.02358},
  year   = {2021}
}
R2 v1 2026-06-23T16:01:56.491Z