Magnetic field control and swift heavy ion beam assisted tuning of resistive switching properties of BSFO/CFO/LNO heterostructures

Abstract

Resistive switching (RS) behavior in mixed oxide insulators has shown a great promise as memristors or non-volatile resistive random-access memory (RRAM) applications. For dilute magnetic oxide multilayers, a novel approach of controlled defects induced and the magnetic field control of RS behavior is proposed. Resistive switching in Bi0.6Sr0.4FeO3 /CoFe2O4 /LaNiO3 (BSFO /CFO /LNO) multilayer heterostructures has been investigated as a case study. All oxide junctions consisting of conducting LaNiO3 (LNO) bottom electrode and BSFO-CFO active layers were fabricated by using chemical solution deposition. A set of samples were irradiated with 150 MeV Ag11+ ions for three different ion fluence of ~ 1×10+11 ions/cm2, 1×10+12 ions/cm2 and 5×10+12 ions/cm2. Polycrystalline phase pure films with smooth, crack free surfaces were observed for pristine and irradiated samples. Optical spectroscopy revealed a decrease in the transmittance upon increasing ion fluence due to increase in the light scattering centres. The optical band gap showed a systematic decrease from 2.09 eV to 1.65 eV with increasing ion fluence. Room temperature I-V characteristics showed consistent and pronounced bipolar switching for all samples below ± 5 V. Upon applied magnetic fields of 0.58 T, the resistive switching ratios were found to increase significantly and were further tuned by 150 MeV Ag11+ ion beam irradiations. The magnetic field control of electrical transport properties in the controlled defect assisted oxide heterojunctions offers new insights to the existing understanding of oxide-based RS mechanism.

Smart alloy metalized novel photonic NEMS photodiode with CuAlV/n-Si/Al junction structure

“…To investigate the dominant current conduction mechanisms in the forward bias I-V region of the produced CuAlV/n-Si/Al NEMS photodiode, SCLC (space charge limited current) analysis [14,16,[68][69][70][71][72][73][74][75][76] was performed by finding varying linear fitting slopes on the different slope zones of forward bias I-V characteristics of the photodiode. Since the thermionic emission (or thermal electron emission) mechanism is not the dominant current conduction mechanism in the forward bias region of Schottky contact diodes due to the absence of a potential barrier height (or negligible) and related depletion layer decreasing in their forward bias regions.…”