Trapped-Ion Quantum Computers - cloud emulator and H-Series devices

The research project, for which this quantum computing access is needed, aims to implement Top-ological Quantum Computing (TQC) by operating and testing topological surface codes and other algorithms related to topological quantum field theories (TQFTs) on Quantinuum H-Series processors and emulators. Errors and noise are always a limiting factor, so this project needs to gain access to a machine with industry leading qubit and gate fidelity, which is essential to implementing the non-standard gates that arise from TQFTs and accurately probing various conjectures arising from geometry and topology that might depend sensitively on certain parameters. Moreover, it is essential for this project to have access to hardware with fully connected qubits, which Quantinuum’s systems also offer, because such TQFT-based gates often need to be applied to arbitrary pairs of qubits. For example, for unitary representations of the braid group, qubits might encode strands, and it would be necessary to be able apply 2-qubit gates to any pair of qubits. Full connectivity significantly reduces transpilation overhead, which otherwise would drastically limit many TQC and TQFT-based algorithms. This project also needs access to a system which supports mid-circuit measurement, fast qubit re-set, and conditional branching, which opens the door to advanced techniques such as error correction, adaptive circuits, and algorithms requiring classical feedback on the fly, which are essential to many algorithms arising in TQC and TQFT. Mid-circuit measurement also allows for measurement-based gates which could present a potential alternative avenue to implement com-plex operations. Finally, mid-circuit measurement will increase efficiency of implementations be-cause qubit can be reused if they are no longer needed. Currently, Quantinuum is the only hard-ware provider offering mid-circuit measurement on a high fidelity trapped-ion machine. To develop proofs of concept that could test potential avenues for quantum advantage, this project needs access to a machine with as many qubits as possible satisfying the above constraints. While Quantinuum’s current H2 machine is already industry leading, access to their upcoming Heli-os QPU could allow for significantly larger calculations owing to its announced approximately 100 qubits. Amount: Quantum/HPC technology Estimated Credits Quantinuum H2 and Helios: 50.000 HQC Quantinuum H-series Emulators: 500.000 eHQC The above HQC estimates represent access to running circuits in Quantinuum’s native gate set. However, while not strictly necessary, direct, pulse-level access to Quantinuum’s machine would al-low for a more efficient implementation of TQFT-based gates by removing the bottleneck of transpilation to native gate sets. Pulse-level access would allow the project to extract maximum efficiency from the quantum resources at hand.