High-Fidelity Phase Insensitive Mølmer-Sørensen Gate on ¹³⁷Ba⁺

High-fidelity two-qubit gates are essential for building a universal quantum computer. Highly performant physical qubits reduce the overhead required for fault-tolerant quantum error correction. Mølmer-Sørensen gates for trapped ion quantum computing can be performed on magnetic field-insensitive ‘clock’ qubits with high-fidelity in both Phase Sensitive (PSMS) and Phase Insensitive (PIMS) configurations. However, there are significant tradeoffs between the two schemes. In this work we discuss the advantages of the PIMS scheme, demonstrate a high-fidelity PIMS gate on ¹³⁷Ba⁺, and characterize leading error sources in our system.