Os16+ and Ir17+ ions as candidates for accurate optical clocks sensitive to physics beyond the standard model

Abstract

We perform detailed calculations of the electronic structure of the ${\mathrm{Os}}^{16+}$ ion and demonstrate that it has several metastable states which can be used for very accurate optical clocks. The clocks are highly sensitive to manifestations of the physics beyond the standard model, such as time variation of the fine-structure constant $\ensuremath{\alpha}$, interaction with scalar and pseudoscalar (axion) dark matter fields, local Lorentz invariance and local position invariance violations, and interaction of atomic electrons with a nucleus mediated by a new boson. The latter can be studied by analyzing the King plot for isotope shifts and its possible nonlinearities since Os has five stable isotopes with zero nuclear spin. Similar calculations for the ${\mathrm{Ir}}^{17+}$ ion spectra demonstrate good agreement between theory and experiment. This helps to validate the method of the calculations and demonstrate that both ions are excellent candidates for the search for new physics.