Metastable Manipulation of the 133Ba+ Qubit

Trapped ions are attractive qubit hosts due to their long coherence times and straightforward manipulation via electromagnetic fields. Future fault-tolerant quantum computers will not only require ultra-high fidelity gate operations, which has been the focus of recent efforts, but also ultrahigh fidelity state preparation and measurement (SPAM), which is currently orders of magnitude lower. We present recent work with the synthetic trapped-ion qubit 133Ba+, a radioactive isotope of barium with a 10.5yr half-life. The spin-1/2 nucleus, visible wavelength electronic transitions, and long-lived 2D5/2 state make this trapped-ion qubit ideal for ultra-high fidelity work. We demonstrate manipulation through a stimulated Raman transition of the 2D5/2 state as a stable qubit.