Multistate nonvolatile memory enabled by opto-electric manipulation based on van der Waals ferroelectric semiconductor

In the era of big data and artificial intelligence, the rising demand for data-intensive processing, alongside the need to minimize system complexity, underscores the growing importance of non-volatile memory with electro-optic capabilities. Against this backdrop, significant exploration of advanced memory architectures has been spurred. Here, we present a ferroelectric semiconductor ferroelectric field-effect transistor (FeS-FeFET) whose channel and gate dielectric are both ferroelectric materials. It establishes a dual-mode, multi-state non-volatile optoelectronic memory. Through investigation of in-plane polarization in the ferroelectric channel and out-of-plane polarization in the ferroelectric gate dielectric, the device demonstrates two-level electrical programming and erasing, along with robust optoelectronic memory characteristics. Specifically, the device exhibits four distinct resistance states under a 5 V operating voltage, with programming speeds up to 40 ns, an optical memory capacity of 7 bits, a maximum on/off current ratio of 10⁴, and a retention time exceeding 10³ s. This work presents promising advancements for future high-density, low-power technologies, with broad applications in high-density data memory and neuromorphic computing.