“…Since the physical memristor has been fabricated by Hewlett-Packard Lab in 2008 [Strukov et al, 2008], it has attracted much attention of researchers. Due to its nonvolatility, nanosize, and low power consumption, memristor can be applied in various fields, such as nonvolatile memory [Strukov, 2016], neural networks [Soudry et al, 2015;Duan et al, 2015], nonlinear chaotic circuits [Zhou et al, 2016;Wu & Wang, 2016;Yuan et al, 2016;Wang et al, 2017;Corinto & Forti, 2017;Ma et al, 2017], and so on.…”