Perturbed ferromagnetic chain: Tunable test of hardness in the transverse-field Ising model

Quantum annealing in the transverse-field Ising model (TFIM) with open-system dynamics is known to use thermally assisted tunneling drive computation. However, it still subject debate whether quantum systems presence of decoherence are more useful than those using classical We contribute this by introducing perturbed ferromagnetic chain (PFC), a frustrated subsystems where degree frustration scales inversely perturbation introduced tunable parameter. This gives us an easily embeddable gadget whereby problem hardness can be tuned for constant size. outline properties PFC and compare spin-vector Monte Carlo (SVMC) variants adiabatic master equation. demonstrate that SVMC methods get trapped exponentially large first-excited-state manifold when solving problem, whereas evolution remains lowest energy eigenstates. results significant differences ground-state probability either or TFIM.