Comment on "$Φ$ memristor: Real memristor found" by F. Z. Wang, L. Li, L. Shi, H. Wu, and L. O. Chua [J. Appl. Phys. 125, 054504 (2019)]

Abstract: Wang et al. claim [J. Appl. Phys. 125, 054504 (2019)] that a current-carrying wire interacting with a magnetic core represents a memristor. Here, we demonstrate that this claim is false. We first show that such memristor "discovery" is based on incorrect physics, which does not even capture basic properties of magnetic core materials, such as their magnetic hysteresis. Moreover, the predictions of Wang et al.'s model contradict the experimental curves presented in their paper. Additionally, the theoretical pinched hysteresis loops presented by Wang et al. can not be reproduced if their model is used, and there are serious flaws in their "negative memristor" emulator design. Finally, a simple gedanken experiment shows that the proposed $\Phi$-memristor would fail the memristor test we recently suggested in J. Phys. D: Appl. Phys. 52, 01LT01 (2019). The device "discovered" by Wang et al. is just an inductor with memory.