Single-ion fluorescence probing of electro-optic modulator efficiency and Raman coupling in trapped-ion system

Abstract

We present a fluorescence-based method for optimizing electro-optic modulator (EOM) performance using a single trapped ion. By comparing fluorescence from a trapped ion with optical cavity measurements, we determine modulation conditions for optimizing optical sidebands, which is essential for driving various transitions relevant to ion-qubit manipulation. We also observe enhanced fluorescence from a trapped ion when applying high-power pulsed laser without EOM modulation. Since the pulsed laser is used for performing quantum gates on individual ions, this fluorescence signal can serve as a diagnostic tool for aligning the ion with a tightly focused laser beam. These results provide a practical method for optimizing sideband generation and diagnosing spatial beam overlap in trapped-ion quantum systems. © 2025 Korean Physical Society