Exploring Phase-Change Memory: From Material Systems to Device Physics

To deal with the growing demand for data storage and processing, phase-change memory (PCM) provides one of the most promising candidates for next-generation nonvolatile data storage and neuromorphic computing applications. A lot of effort has been made toward optimizing the materials and device design; thus, excellent device performances have been achieved including high density, fast switching speed, great endurance, and retention. In addition, the widely tunable optical characteristics of PCMs are irresistibly attractive for optoelectronic or all-optical applications with unprecedented bandwidth, low energy consumption, and multilevel data storage. Herein, the materials system and switching mechanisms on experimental and modeling methods for PCM designs and applications are discussed. Electric-domain and optical-domain PCM-based artificial synapses/neurons and their applications in neuromorphic computing are also reviewed. Finally, the future prospects and challenges of PCM-based applications on materials, devices, algorithms, and system levels are highlighted.