Nonvolatile memristor based on heterostructure of 2D room-temperature ferroelectric α-In2Se3 and WSe2

Two-dimensional(2D) ferroelectricity is considered to have significant potential for information storage in the future. Semiconducting ferroelectrics that are stable at room temperature afford many possibilities for the assembly of various high-performance heterostructures and fabricating multifuntional devices.Herein, we report the synthesis of a stable van der Waals(vd W) single-crystal semiconductor α-In2 Se3.Piezoresponse force microscopy(PFM) measurements demonstrated the out-of-plane ferroelectricity in ～15 layers α-In2 Se3 at room temperature. Both ferroelectric domains with opposite polarization and the tested amplitude and phase curve proved that this semiconductor exhibits hysteresis behavior during polarization.In the α-In2Se3/WSe2vertical heterostructure device, the switchable diode effect and nonvolatile memory phenomenon showed a high on/off ratio and a small switching voltage. The distinct resistance switches were further analyzed by band alignment of the heterostructure under different polarizations by first principle calculations. Nonvolatile memory based on vd W ferroelectric heterostructure could provide a novel platform for developing 2 D room-temperature ferroelectrics in information storage.