Multi-state storage and optoelectronic logic gates implementation with van der Waals ferroelectric field effect transistors

To overcome the von Neumann bottleneck, van der Waals ferroelectric field-effect transistors (vdW FeFETs) offer a promising route by integrating nonvolatile storage and logic computation in a single device. In this work, a vdW FeFET is fabricated to achieve multi-resistance states and optoelectronic logic gates, which are realized by integrating an interrelated ferroelectric semiconductor α - In 2 Se 3 and an out-of-plane (OOP) ferroelectric gate β - InSe . The device exhibits four distinct and stable resistance states enabled by the OOP polarization of the gate dielectric, together with partial polarization of the upper and lower surfaces of the channel semiconductor. By exploiting the OOP polarization of two ferroelectric materials, the FeFET achieves direct switching among four storage states via gate voltage modulation. Furthermore, by leveraging the bulk photovoltaic effect of α - In 2 Se 3 , the device can be utilized as an optoelectronic logic gate, capable of executing AND and OR operations. This integration of multi-state memory and optoelectronic storage-computing within a single FeFET presents a promising strategy for advancing artificial intelligence, optical communication, and edge computing technologies.