Three-dimensional Micromotion Compensation Protocols for an RF Ion Trap

We propose and demonstrate four procedures for three-dimensional micromotion compensation by combining two methods: the RF-photon correlation method and the displacement method based on trap RF amplitude modulation. In ion traps, the structure of the electrodes or the vacuum chamber may restrict the laser beam incidence direction, and causes the limitation in the compensation scheme. We present four protocols, ensuring that at least one of them can be applied to experimental systems with various individual constraints. We also discuss the compensation accuracy and practical applicability of each of these four approaches. This work provides a practical guideline for performing full three-axis micromotion compensation and contributes to the advancement of endcap traps, which are highly suitable for single-ion trapping.