Benchmarking with leakage heralded measurements on the Quantinuum Helios processor

We report on using leakage heralded measurement to benchmark quantum operations on Helios, Quantinuum's 98-qubit trapped-ion quantum computer based on the Quantum Charge-Coupled Device (QCCD) architecture. On Helios, leakage errors can be detected using a measurement protocol that utilizes cabinet shelving for the Barium qubit without the need for additional ancilla or two-qubit gates. This protocol returns a ternary result (0, 1, or L) and allows, for instance, resolution of state-dependent leakage contributions to error channels for a given quantum operation. We discuss leakage heralding using this protocol as well as benchmarking results for various quantum operations performed on Helios.