Quantum Control of a Trapped Ion using a Stimulated Brillouin Scattering Laser

Trapped ions are natural qubit candidates for quantum information processors and sensors, but high-fidelity quantum operations require high quality laser oscillators. In typical trapped-ion experiments, high finesse, free-space optical cavities made of ultralow expansion (ULE) glass are used to reduce the emission linewidth of commercial lasers to the level of the ion’s natural linewidth. Integration of these narrow laser systems into compact or scalable platforms presents a challenge, since it is not currently possible to fabricate integrated photonic resonators with quality factors as high as those in ULE cavities. In this work, we demonstrate the application of the stimulated Brillouin scattering (SBS) nonlinearity in a fiber-based cavity with a quality factor similar to those of integrated photonic resonators to achieve lasing at a linewidth comparable to that of a ULE cavity-stabilized laser. Additionally, we apply a novel technique to suppress temperature fluctuation of the central frequency of the fiber resonator to enable precise control of ions. The development of an ultranarrow laser compatible with integrated photonic resonators is a key part of the design of future portable quantum technologies based on trapped ions.