Non-Markovian transient Casimir-Polder force and population dynamics on excited- and ground-state atoms: Weak- and strong-coupling regimes in generally nonreciprocal environments

Abstract

The transient Casimir-Polder force on a two-level atom introduced into a three-dimensional, inhomogeneous, generally non-reciprocal environment is evaluated using non-Markovian Weisskopf-Wigner theory in the strong and weak coupling regimes. Ground-state and excited atoms are considered as two separate initial-value problems, and both the short-time and long-time atomic population and force are evaluated. The results are compared with various Markov approximation of the Weisskopf-Wigner theory, and with previous Markov results from the Heisenberg picture.