Evidence of coherent quantum annealing

Recent experiments have demonstrated the ability to simulate programmable quantum spin systems at finite temperature using quantum annealers. In this work we examine the 1D quantum Ising chain, probing anneal times down to the 10 nanosecond range. For fast anneals we see signatures of closed-system quantum annealing: In large systems we see quantum Kibble-Zurek scaling, with theoretically predicted kink statistics up to the third cumulant, independent of system temperature. In small systems we see Landau-Zener scaling characteristic of an excitation mechanism dominated by a single anticrossing.