Prospects for atomic clocks based on large ion crystals

We investigate the feasibility of precision frequency metrology with large ion crystals. For clock candidates with a negative differential static polarizability, we show that micromotion effects should not impede the performance of the clock. Using Lu⁺ as a specific example, we show that quadrupole shifts due to the electric fields from neighboring ions do not significantly affect clock performance. We also show that effects from the tensor polarizability can be effectively managed with a compensation laser at least for a small number of ions (10³). These results provide new possibilities for ion-based atomic clocks, allowing them to achieve stability levels comparable to neutral atoms in optical lattices and a viable path to greater levels of accuracy.