Benchmarking quantum annealing dynamics: the Spin-Vector Langevin model*

 The classical Spin-Vector Monte Carlo model (SVMC) is a reference benchmark for the performance of a quantum annealer. As a Monte Carlo method is unsuited for an accurate description of the annealing dynamics in real-time. We introduce the Spin Vector Langevin (SVL) model as a benchmark in which the time evolution is described by Langevin dynamics.  

 SVL is shown to provide a more stringent test than SVMC for the identification of quantum signatures in the performance of quantum annealing devices, as we illustrate by describing the Kibble-Zurek scaling associated with dynamics of symmetry breaking in the transverse field Ising model, recently probed using D-Wave machines. Specifically, we show that D-Wave data is reproduced by the SVL model.