Observation of single-defect memristor in an MoS 2 atomic sheet

• Published in: Nature nanotechnology Vol. 16; no. 1; p. 58
• Main Authors: Hus, Saban M, Ge, Ruijing, Chen, Po-An, Liang, Liangbo, Donnelly, Gavin E, Ko, Wonhee, Huang, Fumin, Chiang, Meng-Hsueh, Li, An-Ping, Akinwande, Deji
• Format: Journal Article
• Language: English
• Published: England 01-01-2021
• ISSN: 1748-3395

Non-volatile resistive switching, also known as memristor
effect, where an electric field switches the resistance states of a two-terminal device, has emerged as an important concept in the development of high-density information storage, computing and reconfigurable systems
. The past decade has witnessed substantial advances in non-volatile resistive switching materials such as metal oxides and solid electrolytes. It was long believed that leakage currents would prevent the observation of this phenomenon for nanometre-thin insulating layers. However, the recent discovery of non-volatile resistive switching in two-dimensional monolayers of transition metal dichalcogenide
and hexagonal boron nitride
sandwich structures (also known as atomristors) has refuted this belief and added a new materials dimension owing to the benefits of size scaling
. Here we elucidate the origin of the switching mechanism in atomic sheets using monolayer MoS
as a model system. Atomistic imaging and spectroscopy reveal that metal substitution into a sulfur vacancy results in a non-volatile change in the resistance, which is corroborated by computational studies of defect structures and electronic states. These findings provide an atomistic understanding of non-volatile switching and open a new direction in precision defect engineering, down to a single defect, towards achieving the smallest memristor for applications in ultra-dense memory, neuromorphic computing and radio-frequency communication systems
.