Dual-Input Two-Dimensional Floating-Gate Memory With Intrinsic Stochasticity for Secure Information Processing

2D materials have enabled diverse electronic and optoelectronic devices, yet intrinsic stochastic behaviors are commonly regarded as detrimental to device reliability and controllability. Here, we demonstrate a dual-input 2D floating-gate memory that deliberately harnesses intrinsic stochastic optoelectronic responses as a functional degree of freedom for secure information processing. By integrating electrical gating and optical excitation within a Bi₂O₂S/h-BN/graphene heterostructure, the floating-gate device simultaneously achieves non-volatility, multilevel programmability, and reconfigurable device-intrinsic stochastic conductance responses. The memory exhibits a high on/off current ratio (>10⁶), a wide memory window (83.4%), long retention (10⁴ s), and robust endurance (>2000 cycles), enabling stable hardware-level extraction of physical features. As a representative application, the stochastic optoelectronic features are combined with standard cryptographic primitives to realize reversible text and image encryption with pronounced diffusion and avalanche characteristics, while session-level freshness is naturally supported to mitigate replay attacks and key reuse. Beyond cryptography, this work establishes a materials-enabled strategy for transforming intrinsic stochasticity in 2D floating-gate devices from an undesired effect into a useful functionality, opening new opportunities for multifunctional memory and secure information processing architectures.