Quantum correlation of channel-confined ions in graphene-based transistors for energy-efficient neuromorphic chips

Based on ab initio molecular dynamics simulations, we explain how graphene-based ion transistors work, using channels filled with K⁺ ions. Our results show that electrons in graphene allow confined ions to influence each other over long distances. This explains why the transistor responds sensitively to changes in ion density, which are controlled by the gate voltage. The ON/OFF switching behavior comes from the competition between π–π stacking and cation–π interactions, which changes with ion density. The increase in ion transport efficiency—also called signal amplification—is caused by the ions moving together in a coordinated way that depends on their density. Additionally, when ions outside the channel resonate with those inside, rapid dehydration occurs. This leads to very fast ion movement through the transistor. These atomic-scale insights can help guide the design of future ultra-low-energy neuromorphic chips.