Synergistic Effects of Interfacial Electric Fields and Cryogenic Temperatures on the Performance of Li‐Ion Electronic Synapses

The cryogenic neuromorphic computing (NC) system is considered a potential future of computing due to its low energy consumption and high parallel computation power when combined with quantum computing (QC). However, the electronic synapse in this system, which serves as the memory function, should be positioned as close as possible to the QC to store the information generated by the QC, and it must operate effectively at cryogenic temperatures. In this work, the properties of the LiCoO 2 (LCO) electronic synapse at both cryogenic and room temperatures have been thoroughly investigated. The Li‐ion nanoreservoir, Al‐rich LiCoO 2 (LACO), is believed to perform three major functions: stabilizing the Li ions, decreasing the interfacial electric field, and reducing the leakage current. Additionally, cryogenic temperatures slow down Li‐ion and electron diffusion, enhancing the influence of the electric field. As a result, the bottom electrode and temperature factors improve the performance of the LCO electronic synapse in terms of memory window (from ≈1.6 to ≈423), linearity (long‐term‐potentiation linearity from 3.89 to 0.97, long‐term‐depression linearity from −4.56 to −3.58), and spike‐time‐dependent plasticity (STDP) characteristics (a twofold improvement in the STDP window and a 1.5‐times faster spike response time).