Fig. 2: Electric field-driven reversible phase transitions in two-dimensional (2D) materials.
From: Advanced AI computing enabled by 2D material-based neuromorphic devices

a Representative schematic of layered and tunnel polymorphs of MnO2 and, Mn3O4. b Optical microscope image of 2D K-MnO2 crystals on a sapphire substrate37. c I–V cycle from a graphite/K-MnO2/graphite memristive device. d Schematics depict the condition when panel i with no bias is applied and panel ii when bias is applied.