A 2D Heterostructure‐Based Multifunctional Floating Gate Memory Device for Multimodal Reservoir Computing

Abstract

The demand for economical and efficient data processing has led to a surge of interest in neuromorphic computing based on emerging two‐dimensional (2D) materials in recent years. As a rising van der Waals (vdW) p‐type Weyl semiconductor with many intriguing properties, tellurium has been widely used in advanced electronics/optoelectronics. However, its application in floating gate memory devices for information processing has never been explored. Herein, we report an electronic/optoelectronic floating gate memory device enabled by tellurium‐based 2D vdW heterostructure for multimodal reservoir computing. When subjected to intense electrical/optical stimuli, our device exhibits impressive nonvolatile electronic memory behaviors including ∼108 extinction ratio, ∼100‐ns switching speed, >4000 cycles, >4000‐s retention stability, and nonvolatile multi‐bit optoelectronic programmable characteristics. When the input stimuli weaken, the nonvolatile memory degrades into volatile memory. Leveraging these rich nonlinear dynamics, we demonstrate a multimodal reservoir computing system with high recognition accuracy of 90.77% for event‐type multimodal handwritten digit‐recognition.This article is protected by copyright. All rights reserved

Synthesis of air-stable 1T-CrS2 thin films and their application in high-performance floating-gate memory

“…The 532 nm laser is often used to test the photoelectric properties of MoS 2 and has excellent light absorption intensity in the visible light band. 10,15,53 To assess the optical storage potential, applying a +60 V gate voltage for 10 ms (Fig. 4e) puts the device in HRS, then subjected the device to periodic light pulses using a 532 nm laser at an intensity of 27.5 mW cm −2 for 1 s with a 5 s interval.…”

“…6,7 This has prompted the search for new memory technologies, like those utilizing ultrathin two-dimensional (2D) materials, including graphene, hexagonal boron nitride, and transition metal dichalcogenides (TMDs). 8–11 These materials, known for their unique layered structures and clean interfaces, form van der Waals (vdW) heterostructures, ideal for next-generation electronic and optoelectronic devices. 12–17 Memory devices employing 2D crystal floating gates have shown exceptional data retention and durability, despite variations in performance metrics such as on/off ratios and memory window sizes.…”

An Ultrafast Multibit Memory Based on the ReS2/h-BN/Graphene Heterostructure

“…Previous studies 30,38 have demonstrated that direct tunneling is dominant at small gate voltages, whereas the Fowler− Nordheim (F−N) mechanism dominates the tunneling process under large gate voltages. The current equation for F−N tunneling can be expressed as 33 = * * i k j j j j j j j y…”

“…Figure 3d shows an F−N plot of the I−V curve obtained from the tests, and the linear relationship between them indicates that the F−N tunneling mechanism dominates in our device. 30,38,40,41 Electrical and Optical Multilevel Storage. Our device has a high erasing/programming current ratio, which enables multilevel storage in a single memory cell.…”

Wavelength-Dependent Multistate Programmability and Optoelectronic Logic-in-Memory Operation from the Narrow Bandgap pNDI-SVS Floating Gate

“…By employing such materials including both organic − and inorganic − substances, the degree to which charge is trapped in the floating gate can be controlled based on the exposure to light. This capability opens up possibilities for devices such as optical memories, where both optical detection and memory operations can occur simultaneously, photonic logic circuits − utilizing light as an input for logical operations, or photonic synapses − where light serves as the stimulus for memory components.…”