## Volatile and Non-Volatile Memristor Characterization ### Overview The image presents comparative electrical characterization of volatile and non-volatile memristors, supported by SEM micrographs of material layers. Two primary graphs per memristor type show current-voltage (I-V) relationships and cycle-dependent performance, with material composition details provided in the central SEM images. ### Components/Axes **Volatile Memristor (Left Panel):** - **Graph a (Top):** - X-axis: Voltage (V) from 0 to 2 V - Y-axis: Current (A) from 1e-9 to 1e-6 A (log scale) - Legend: Cycle 1 (solid purple), 2-49 (dashed purple), Cycle 50 (solid dark purple) - Spatial: Legend positioned right-aligned - **Graph b (Bottom):** - X-axis: Cycles (1e6 to 2e6) - Y-axis: Current (A) from 1e-9 to 1e-7 A (log scale) - Markers: - Squares: @0.1V before - Circles: @2V - Triangles: @0.1V after - Spatial: Markers clustered at bottom **Non-Volatile Memristor (Right Panel):** - **Graph a (Top):** - X-axis: Voltage (V) from -6 to 4 V - Y-axis: Current (A) from 1e-10 to 1e-4 A (log scale) - Legend: Cycle 1 (solid blue), Cycle 1000 (dashed blue) - Spatial: Legend positioned right-aligned - **Graph b (Bottom):** - X-axis: Cycles (0 to 5000) - Y-axis: Current (A) from 1e-13 to 1e-4 A (log scale) - Markers: - Light blue: LRS (Low Resistance State) - Dark blue: HRS (High Resistance State) - Spatial: Markers distributed across cycle axis **Central SEM Images:** - Labeled 1-5 with material identifiers: 1. Ag 2. OGB capped CsPbBr₃ NCs 3. pTPD 4. PEDOT:PSS 5. ITO - Scale bars: 200 nm (top) and 10 nm (bottom) - Spatial: Centered between memristor graphs ### Detailed Analysis **Volatile Memristor:** - **Graph a:** - Cycle 1 shows steep I-V curve with sharp threshold (~0.5 V) - Subsequent cycles (2-49) exhibit reduced current density at same voltages - Cycle 50 demonstrates near-identical performance to Cycle 1 - **Graph b:** - Current increases by ~30% at 2V after 2e6 cycles (triangle markers) - Minimal change at 0.1V before/after (square/triangle markers) **Non-Volatile Memristor:** - **Graph a:** - Cycle 1 shows bipolar switching with hysteresis loop - Cycle 1000 exhibits reduced hysteresis width - Sharp threshold at ~0 V for both cycles - **Graph b:** - LRS dominates early cycles (light blue points) - HRS population increases after ~2500 cycles (dark blue clusters) - Current density decreases by ~100x over 5000 cycles **SEM Correlation:** - Layer 1 (Ag) and Layer 5 (ITO) form metallic electrodes - Layer 2 (OGB capped CsPbBr₃ NCs) likely serves as active switching layer - Layer 3 (pTPD) and Layer 4 (PEDOT:PSS) act as interfacial layers - Average feature size ~10 nm matches nanoscale switching requirements ### Key Observations 1. Volatile memristor shows cyclical performance degradation/recovery 2. Non-volatile device exhibits clear LRS/HRS transition with cycling 3. Material layering suggests optimized interfacial charge trapping 4. Voltage thresholds align with typical memristive switching ranges 5. Current density variations correlate with cycle-dependent aging ### Interpretation The data demonstrates fundamental differences between volatile and non-volatile memristive behavior: - Volatile device shows reversible but cycle-dependent characteristics, suggesting electrochemical redox processes - Non-volatile device exhibits persistent LRS/HRS states with cycling, indicating successful charge trapping - Material composition (particularly OGB-capped perovskite NCs) likely enables nanoscale filament formation - SEM imaging confirms sub-10nm feature sizes critical for high-density memory applications - Bipolar switching in non-volatile device suggests ionic conduction mechanisms - Cycle-dependent current changes indicate potential for endurance testing protocols