Ferroelectrically modulated α-In₂Se₃/ReS₂ heterostructure for sensing-memory-computing devices

To address the von Neumann bottleneck, multifunctional optoelectronic devices integrating sensing and computing capabilities have garnered increasing attention. In this work, we demonstrate a ferroelectric heterojunction phototransistor based on an α-In₂Se₃/ReS₂ stack, which combines sensing, memory, and computation capabilities. By modulating the polarization state of α-In₂Se₃ via gate voltages, the device dynamically tunes the built-in electric field and thereby regulates its conductance state. The device achieves a high responsivity of 17.2 A/W and a specific detectivity of 3.6 × 10¹² Jones, together with excellent nonvolatile retention. Furthermore, it effectively emulates key synaptic behaviors including short-term plasticity, long-term plasticity, paired-pulse facilitation, and experience-dependent learning. When incorporated into neural network models, the device achieves recognition accuracies of 93.7% for handwritten digit classification and 84.0% for clothing recognition. These results underscore the potential of α-In₂Se₃/ReS₂ heterostructures as building blocks for next-generation neuromorphic optoelectronic systems with integrated sensing-memory-computing capabilities.