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The resistive switching effect in individual ferromagnetic filaments in memristive stacks based on ZrO2(Y)/Ni functional layers was studied experimentally. A conductive probe of an atomic force microscope played a role of a movable top electrode of a virtual memristive stack. The features of bipolar-type resistive switching found were related to the rapture and restoring of the filaments containing Ni atoms in the ZrO2(Y) dielectric films and are probably caused by different degree of metallization of the filaments. The filaments fromed were manifested in the images obtained by magnetic force microscopy as single-domain ferromagnetic particles. [ABSTRACT FROM AUTHOR]

The effect of optical illumination in the visible band on the resistive switching in ITO/ZrO2(Y)/n-Si metal—oxide—semiconductor (MOS) structures (including those with Au nanoparticles embedded in the ZrO2(Y) layer) is studied. It is found that the dependence of the logical gap between the resistance states on the photoexcitation intensity had a threshold nature. The logical gap decreases with further increasing photoexcitation intensity above the threshold. This effect is ascribed to the heating of active layers of the MOS structure due to interband optical absorption in the Si substrate. The suppression of resistive switching by photoexcitation at a wavelength of 650 nm (corresponding to plasmon resonance in Au nanoparticles) due to plasmon optical absorption in nanoparticles is observed. [ABSTRACT FROM AUTHOR]

We have studied the resistive switching in memristive structures based on 40-nm-thick yttria-stabilized zirconia (YSZ) films exposed to 6-keV Si+ ion irradiation to a total dose of 5.4 × 1015 cm–2. It is established that the ion irradiation leads to increased stability of the parameters of resistive switching in YSZ based memristive structures. This effect is related to the fact that the diameter of conducting filaments in irradiated structures is limited by lateral dimensions of the region of atomic displacement cascades (i.e., the region occupied by point defects produced by bombarding ions). The oxidation of ion-modified filaments during resistive switching proceeds more effectively and leads to increasing resistance in the high-resistance state of memristive structures. [ABSTRACT FROM AUTHOR]

Conducting ferromagnetic nanosized filaments consisting of Ni atoms are formed in thin ZrO2(Y)/Ni films using an atomic force microscope probe. The contact of the probe to such films (a virtual composite memristor device) exhibits resistive switching of the bipolar type associated with the destruction and restoration of Ni filaments in the ZrO2(Y) film. The region in which the conductive filament emerges onto the surface of the ZrO2(Y) film manifests itself in the magnetic force image as a single-domain ferromagnetic particle. [ABSTRACT FROM AUTHOR]

Abstract—: The effect of optical illumination on the resistive switching in ultrathin (~4 nm) ZrO2(Y) films with embedded single-layer Au nanoparticle arrays 2-3 nm in size is studied via tunneling atomic force microscopy. The ZrO2(Y) films with Au nanoparticles are grown by layerwise magnetron deposition onto glass substrates with a conductive indium-tin-oxide sublayer, followed by annealing at 450°C. An increase in hysteresis due to bipolar resistive switching in the ZrO2(Y) films is observed on the cyclic current-voltage curves of the microscope probe-to-sample contact. The effect is found to manifest itself in a dense Au nanoparticle array (~660 nm) when the contact area is photoexcited through a transparent substrate exposed to the radiation of a semiconductor laser at the plasmon-resonance wavelength. The effect is attributed to the photon-assisted field emission of electrons from Au nanoparticles to the conduction band of ZrO2(Y) in a strong electric field between the microscope probe and the indium-tin-oxide substrate under plasmon-resonance conditions. [ABSTRACT FROM AUTHOR]