Error Suppression in Continuous-time Quantum Computing

Compared to the circuit model of quantum computation, there has been more limited work on Hamiltonian error suppression (HES), described in [Crosson, & Lidar, arXiv:2008:09913v1, 2020]. Building on an idea proposed in [Young et al., Phys. Rev. A88, 062314, 2013], multiple copies k of a small Ising spin model can be linked together via ferromagnetic or anti-ferromagnetic links. This increases the logical system's robustness to error. Numerical methods show that copies connected via anti-ferromagnetic links perform better than those connected via ferromagnetic links in some cases. A protocol enables us to determine for which models anti-ferromagnetic links are beneficial, allowing us to harness this performance improvement. This technique shows promise for increasing the robustness and precision in continuous-time quantum computing.