MEMS scanners for integrating an optical cavity in a segmented ion trap for enhanced qubit readout

In this study utilization of piezoelectrically AlScN driven quasi-static MEMS scanners for stabilizing the length of an optical resonator has been investigated, aiming to enhance spontaneous emission according to the Purcell effect during qubit readout in an ion-trap based quantum processor. To stabilize the length of the optical cavity, the closed-loop controlled translatory motion of the MEMS scanner must be smaller than 0.02 nm, where this requirement results from the used laser wavelength and the finesse of the cavity. Measurements for this purpose have been conducted using a Michelson interferometer and the results show that a stable precise movement of 0.02 nm can be achieved at a driving voltage of 0.07 mV. Additional downscaling of the MEMS scanner is necessary to integrate the cavity into a multi-segmented linear ion trap, requiring further work in design and fabrication. FEM simulation results of new MEMS scanner designs show the achievement of higher device stiffness, so that the movement controllability can be improved. Moreover, a high reflective glass mirror has been developed for the optical cavity as well. The investigation results will be reported in this work.