Guowei Liu, Jiaqi Ding, Ziyu Wan, Jiakun Xue, Yu Zhang, Zhenqi Gong, Chengyuan Peng, Wenpei Shi, J. Su, Jiangnan Xia, Huipeng Chen, Lang Jiang, Lei Liao, Yuanyuan Hu
Bayesian neural networks (BNNs) enable trustworthy edge intelligence by quantifying predictive uncertainty. However, hardware BNN implementations face a bottleneck: digital approaches suffer from high latency, while memristors are limited by the intrinsic coupling between their conductance state (mean) and stochastic noise (variance). Here we report a coupled dual-channel memristor (CDCM) based on an ion gel/ZnO heterostructure that breaks this fundamental trade-off. Utilizing vertical ion-gating to establish two tunable memristive channels, our device defines synaptic weight as the differential conductance between the two channels. This architecture enables the hardware-native orthogonal control over the synaptic weight mean (μ) and standard deviation (σ), allowing for the precise synthesis of decoupled Gaussian weights. We validate our approach with a hardware-calibrated BNN for multimodal human activity recognition, achieving 79.08% accuracy while reliably detecting unseen activities as out-of-distribution anomalies. This work provides a scalable, physics-driven paradigm for energy-efficient, inherently trustworthy probabilistic computing. Probabilistic computing, such as Bayesian neural networks, quantifies predictive uncertainty to prevent overconfident predictions. Liu et al. demonstrate a coupled dual-channel memristor that independently controls synaptic weight mean and variance, enabling trustworthy AI in safety-critical edge applications.