Characterization of an Integrated, Cryogenic-Compatible Shuttling Controller for Scaling Trapped-Ion Quantum Computers*

Ion traps offer unique advantages for scaling quantum computing circuits, offering all-to-all connectivity, excellent error rates, and fundamentally equal properties for each ion operated as a qubit. One challenge encountered in scaling ion traps to even larger qubit numbers stems from the amount of control signals needed for ion shuttling operations. Future ion traps will require numerous signals for shuttling, complicating scalability due to limited wiring capacity at cryogenic temperatures. This wiring introduces significant thermal load, which impacts the cooling budget necessary for proper operation.

We present an integrated ion shuttling controller, which can be placed below the ion trap. This drastically reduces the amount of wiring needed from outside the cryostat. The shuttling controller itself can be controlled with a limited number of digital signals and analog supply voltages, and provides multiple different control voltages. These signals are generated by individually controllable digital-to-analog converters (DACs). The chip is designed to be operated at 4.2 K, and the measurement setup to characterize the individual DACs at cryogenic temperatures is described in detail. Measurements of the output waveform, noise parameters, and linearity are shown at room- and cryogenic temperatures.