Nanoscale Imaging and Control of Volatile and Non-Volatile Resistive Switching in VO 2

• Published in: Small (Weinheim an der Bergstrasse, Germany) Vol. 16; no. 50; p. e2005439
• Main Authors: Shabalin, Anatoly G, Del Valle, Javier, Hua, Nelson, Cherukara, Mathew J, Holt, Martin V, Schuller, Ivan K, Shpyrko, Oleg G
• Format: Journal Article
• Language: English
• Published: Germany Wiley Blackwell (John Wiley & Sons) 01.12.2020
• Subjects: VO 2 films; resistive switching; metal-insulator phase transition; resistive memory; X-ray imaging; oxygen vacancies
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202005439

Control of the metal-insulator phase transition is vital for emerging neuromorphic and memristive technologies. The ability to alter the electrically driven transition between volatile and non-volatile states is particularly important for quantum-materials-based emulation of neurons and synapses. The major challenge of this implementation is to understand and control the nanoscale mechanisms behind these two fundamental switching modalities. Here, in situ X-ray nanoimaging is used to follow the evolution of the nanostructure and disorder in the archetypal Mott insulator VO during an electrically driven transition. Our findings demonstrate selective and reversible stabilization of either the insulating or metallic phases achieved by manipulating the defect concentration. This mechanism enables us to alter the local switching response between volatile and persistent regimes and demonstrates a new possibility for nanoscale control of the resistive switching in Mott materials.