Vacuum gap atomic switch with improved controllability of quantized conduction states and low transition energy

To maximize the multilevel data storage capability for high-density memory applications, precise control of quantized conduction with ultralow transition energy is required. We report the quantized conduction in Ag/Ag2S/vacuum conductive-bridge random access memory under various pulse conditions to regulate atomic motion at room temperature. Using stochastic analysis, we unveil a pulse condition for supplying the optimal energy that allows precise atom detachment and has a high dissolution probability. In addition, we calculate the transition energy required to change each quantized state for an Al2O3 electrolyte and vacuum gap. We determine a large transition energy of Ag in Al2O3 (8–1 mJ), hindering the precise control of quantized conduction, whereas the transition energy of Ag in vacuum is relatively low (397–95 nJ), enabling proper atomic motion.