Memristive Properties of Structures Based on (Co41Fe39B20)x(LiNbO3)100–x Nanocomposites

Resumo

The current‒voltage characteristics of the metal/nanocomposite (NC)/metal structures based on (Co₄₁Fe₃₉B₂₀)_x(LiNbO₃)_100–x NCs 2.4 and 3 μm thick are investigated in the fields of up to ~10⁴ V/cm. The structures are synthesized via ion-beam sputtering of a composite target, in which NCs of different composition are formed in the single cycle at x = 5‒48 at %. The memristive effect (ME) manifesting itself during resistive switching of structures and the storage of incipient states has been detected at x ≈ 10 at %. It is ascertained that the ME depends weakly on used metal (Cu or Cr) contacts and the NC layer thickness, the number of switching cycles (without degradation) exceeds 10⁵, and the ratio between the resistances of high- and low-resistance states, i.e., the R_off/R_on ratio, reaches approximately 65. The detected ME is explained by the fact that oxygen vacancies substantially affect the tunneling conductance of metal-granule chains determining the electric resistance of structures below the percolation threshold.