Hyper-Ramsey spectroscopy with probe-laser-intensity fluctuations

Abstract

We examine the influence of probe-laser-intensity fluctuations on hyper-Ramsey spectroscopy. We assume, as is appropriate for relevant cases of interest, that the probe-laser intensity $I$ determines both the Rabi frequency ($\ensuremath{\propto}\sqrt{I}$) and the frequency shift to the atomic transition ($\ensuremath{\propto}I$) during probe-laser interactions with the atom. The spectroscopic signal depends on these two quantities that covary with fluctuations in the probe-laser intensity. Introducing a simple model for the fluctuations, we find that the signature robustness of the hyper-Ramsey method can be compromised. Taking the ${\mathrm{Yb}}^{+}$ electric octupole clock transition as an example, we quantify the clock error under different levels of probe-laser-intensity fluctuations.