Abstract: Quantum annealing has been shown to be a powerful tool for both simulation of quantum systems and combinatorial optimisation at the scale of a few thousand superconducting qubits. The hardware is however currently limited both by limited coherence and by the lack of terms in the interacting part of the Hamiltonian other than the two-body longitudinal ZZ interaction. Here I will demonstrate how the addition of new terms such as the XX interaction can significantly enhance the value of the minimum gap at perturbative avoided crossings, thereby enhancing the ground-state probability for a given annealing rate [1,2]. I will further describe our experimental work on the use of coherent phase-slips in superconducting nanowires [3,4] which is a route towards implementing YY interactions.

[1] Feinstein et al. arXiv:2203.06779
[2] Feinstein et al. arXiv:2402.13811
[3] Potter et al. Phys. Rev. App. 19 024002 (2023)
[4] Potter, J. A. PhD thesis, UCL (2021)