Extensive manipulation of transition rates and substantial population inversion of rotating atoms inside a cavity

Abstract

We investigate the transition rates of a centripetally accelerated atom inside a high-quality cavity and show that they can be extensively tuned by adjusting the cavity resonance and the rotation frequency. Crucially, while inertial atoms cannot be excited in vacuum, rotation induces spontaneous excitation via the circular Unruh effect, with the cavity serving only as an amplifier. Using experimentally feasible parameters, we demonstrate that, in one scenario, the excitation rate can reach $\sim 10^7~\mathrm{s}^{-1}$ while emission remains negligible, enabling substantial population inversion. In another scenario, both excitation and emission can simultaneously attain $\sim 10^7~\mathrm{s}^{-1}$, corresponding to millions of transitions per second for a single atom. These findings highlight a powerful method for manipulating atomic transition rates for quantum applications and open a promising route toward experimental verification of the circular Unruh effect with state-of-the-art quantum technologies.