Out-of-time-order correlators in the one-dimensional XY model

Jia-Hui Bao,Cheng-Yong Zhang

Figure 7. Fitting results for the universal form and numerical data of Cxx. We select three models with different vB ; note that all other models of OTOC with nonlocal operators have also been verified. The outside dots represent numerical data obtained by calculating the OTOC along velocity-fixed rays where v = 1.1, 1.2, and 1.5 respectively. The solid lines are fitting forms of −at + b, and a is the velocity-dependent Lyapunov exponents λL(v) that we need to extract. The inset shows how these three sets of extracted data fitted with $\sim {(v-{v}_{B})}^{1+p}$ as a function of v. We observe that the numerical data fits quite well.