Memristive systems can provide a novel strategy to conquer the von Neumann bottleneck by evaluating information where data are located in situ. To meet the rising of artificial neural network (ANN) demand, the implementation of memristor arrays capable of performing matrix multiplication requires highly reproducible devices with low variability and high reliability. Hence, we present an Ag/CuO/SiO₂/p-Si heterostructure device that exhibits both resistive switching (RS) and negative differential resistance (NDR). The memristor device was fabricated on p-Si and Indium Tin Oxide (ITO) substrates via cost-effective ultra-spray pyrolysis (USP) method. The quality of CuO nanoparticles was recognized by studying Raman spectroscopy. The topology information was obtained by scanning electron microscopy. The resistive switching and negative differential resistance were measured from current–voltage characteristics. The results were then compared with the Ag/CuO/ITO device to understand the role of native oxide. The interface barrier and traps associated with the defects in the native silicon oxide limited the current in the negative cycle. The barrier confined the filament rupture and reduced the reset variability. Reset was primarily influenced by the filament rupture and detrapping in the native oxide that facilitated smooth reset and NDR in the device. The resistive switching originated from traps in the localized states of amorphous CuO. The set process was mainly dominated by the trap-controlled space-charge-limited; this led to a transition into a Poole–Frenkel conduction. This research opens up new possibilities to improve the switching parameters and promote the application of RS along with NDR.

Tin sulfides are promising materials in the fields of photoelectronics and photovoltaics because of their appropriate energy bands. However, doping in SnS₂ can improve the stability and robustness of this material in potential applications. Herein, we report the synthesis of SnS₂ nanoflakes with Zn doping via simple hydrothermal route. The effect of doping Zn was found to display a huge influence in the structural and crystalline order of as synthesized SnS₂. Their optical properties attest Zn doping of SnS₂ results in reduction of the band gap which benefits strong visible-light absorption. Significantly, enhanced photoresponse was observed with respect to pristine SnS₂. Such enhancement could result in improved electronic conductivity and sensitivity due to Zn doping at appropriate concentration. These excellent performances show that Sn_1−xZn_xS₂ nanoflakes could offer huge potential for nanoelectronics and optoelectronics device applications.

In this work, the ferromagnetic states of Mn-doped p-type silicon samples were investigated. Two different types of ferromagnetic states have been observed in Si (Mn, B). The samples with a relatively high concentration of Mn revealed a ferromagnetic state with a Curie temperature above room temperature, and that ferromagnetism was due to the Mn _x B _y ferromagnetic clusters. The samples with a moderate concentration of Mn at low temperatures revealed a ferromagnetic state that was mediated by carriers (holes). The samples demonstrated the anomalous Hall effect at temperatures below 100 K and had a negative magneto-resistivity peak at a temperature close to the Curie temperature. The thermal diffusivity measurements demonstrated the existence of a second-order phase transition in the samples with a moderate Mn concentration. The specific heat’s critical exponent α = 0.5, determined from the thermal diffusivity measurements, confirmed the long-range nature of the magnetic exchange interaction in these samples.

We have presented a study of the bipolar resistance switching characteristics in the Ag/ZnO/Pt cell. This switching is accompanied by a change in intensity of the photoluminescence emission at 3.33 eV which is attributed to zinc vacancy related transitions in ZnO film. Besides voltage-driven resistance switching phenomena, a transition from a high-resistance state to a lower one is observed under laser illumination at low temperature. These results demonstrate that the bipolar resistance switching can originate due to an electron trapping/de-trapping process at zinc-vacancy defects localized in the interface layer. The Mott metal-insulator transition is proposed as a possible mechanism of the memory effect.