Giant Ferroelectric Domain Wall Conductance in MoS2/PbTiO3 Heterostructure for High-Density Memory

Abstract

Abstract Domain wall (DW) electronics hold promise for high-density computing, but their implementation is limited by low read currents and high operating voltages in bulk ferroelectric oxides. Here, we present a monolayer molybdenum disulfide (MoS2)/PbTiO3 (PTO) van der Waals (vdW) heterostructure that overcomes these limitations. By integrating a monolayer MoS2 capping layer, we read out giant DW conductance with microampere (μA)-level currents, exceptional retention (>360 h), and an ultralow reading turn-on voltage (∼0.36 V). This giant DW conductance is attributed to local electrostatic doping of the overlaying MoS2 by bound charges accumulated at the DWs, which drastically minimizes the interfacial Schottky barrier for enhanced electron transport. A “nanobubble” domain engineering strategy is further implemented upon these DW-induced conductive channels, yielding quasi-one-dimensional (quasi-1D) conductive states (∼20 nm in diameter) for high-density storage. These results establish a platform with nanometer-scale spatial conduction control, promising for next-generation ultrahigh density reconfigurable nanoelectronics.