Light assisted multilevel resistive switching effect and logic calculation in Cr-doped La₂CoMnO₆-based memristor

Memristor-based architectures hold great potential for future computing systems. However, the reliance on monotonous electrical input to regulate resistance limits the possibilities for high-density storage and multifunctional integration. In this work, we report a multi-functional memristor based on optical and electrical modulation, utilizing double perovskite oxide materials. La₂CoMn_1−xCr_xO₆ (x = 0, 0.15, 0.25, 0.35) films were fabricated on a LaNiO₃/SiO₂/Si conductive heterojunction via the sol–gel method. Among the different Cr doping concentrations, x = 0.25 (25% Cr) was found to be the optimal condition, enhancing both surface quality and resistive switching (RS) performance in the La₂CoMn_1−xCr_xO₆-based films. For the first time, ten distinct resistance states were achieved in an Au/La₂CoMn_0.75Cr_0.25O₆(Cr-LCMO-25)/LaNiO₃/SiO₂/Si device, driven by varying light intensity (650 nm). These states remained stable for 12,000 s and over 450 cycles, demonstrating excellent multilevel RS memory performance in the Cr-LCMO-25-based device. The RS behavior followed the oxygen vacancy (OV)-controlled space charge-limited current model. Cr doping increased the OV concentration, which in turn enhanced the RS behavior. Additionally, photoinduced carriers at the Au/Cr-LCMO-25 interface modulated the Schottky-like barrier, further influencing the multilevel RS behavior. Importantly, complex logic operations, including AND, OR, NOT, and XNOR, were successfully performed using both electrical and optical inputs. This study offers a promising approach to increase memory density, simplify logic circuits, and create lead-free double perovskite-based multifunctional memristors.