Multi-valued logic system: new opportunities from emerging materials and devices

Multi-valued logic (MVL) is considered as a key enabler for next-generation and high-information-density digital electronics. While the conventional approaches to MVL systems rely on circuit-level design and implementation, the emergence of new electronic materials and device concepts now enables the MVL operation in a greatly reduced complexity and with intriguing new functionalities. This review provides a timely overview of such unconventional MVL systems with a strong materials emphasis, focusing on the mechanistic classification and comparison of reported devices, which develops into an evidence-based projection of future developments.