Enhanced Long-Term Memory Properties of ZnO Nanoparticle-Based Optical Synaptic Devices for Neuromorphic Computing. - Jae-Hyeok Oh; Jeong-Hyeon Kim; Hee-Jin Kim; Young-Hyeun Kim; Kyoung-Kook Kim; Sung-Nam Lee (Adv. Intell. Syst., 2023)