Memristor-like behavior and negative resistance in a superconductor/insulator/ferromagnet device with a pinholes-governed interface

We investigate the voltage-current characteristics of a superconductor-insulator-ferromagnet heterostructure, where the insulating layer contains pinhole-defects. The superconducting layer exhibits multiple voltage jumps that are hysteretic with the current sweep direction. This characteristic of the resistive state is due to pinholes that induce local, distinct, coupling regions between the superconducting and ferromagnetic layers which may generate phase-slip lines or vortex channeling. These findings point to a magnetically driven design of a superconductor memristor. Concomitantly, the junctions display both absolute and differential negative resistances below the superconducting critical temperature and current. This anomalous behavior is analyzed using a circuit approach and is attributed to current passing through pinholes within the insulating layer. These two unique effects, which stem from the special topology of the pinholes-governed interface can be applied in superconductor-based switches and memory devices.

Automated summary

We studied the voltage-current characteristics of a superconductor-insulator-ferromagnet heterostructure, with pinhole-defects in the insulating layer. The superconducting layer exhibited multiple voltage jumps that were hysteric with the current sweep direction. This behavior was attributed to pinholes inducing local, distinct, coupling regions between the superconducting and ferromagnetic layers, which could potentially be used in the design of a magnetically driven superconductor memristor. Additionally, the junctions displayed absolute and differential negative resistances below the superconducting critical temperature and current, which was analyzed using a circuit approach and attributed to current passing through pinholes within the insulating layer. These unique effects stemming from the pinhole-governed interface topology could have applications in superconductor-based switches and memory devices.