Journal Article

Purely electronic insulator-metal transition in rutile VO2

Liu, Mingzhao, Ong, Shyue Ping, Zhou, Chenyu, Chen, Chi, Zhu, Yimei, Wang, Zishen, Dean, Mark P. M., Cheng, Shaobo, Li, Xing, Basaran, Ali C., Schuller, Ivan K., Navarro, Henry, Kaur, Jasleen, Meng, Qingping, Rozenberg, Marcelo, Pofelski, Alexandre

2025

Overview

Volatile resistive switching in neuromorphic computing can be tuned by external stimuli such as temperature or electric-field. However, this type of switching is generally coupled to structural changes, resulting in slower reaction speed and higher energy consumption when incorporated into an electronic device. The vanadium dioxide (VO 2 ), which has near room temperature metal-insulator transition (MIT), is an archetypical volatile resistive switching system. Here, we demonstrate an isostructural MIT in an ultrathin VO 2 film capped with a photoconductive cadmium sulfide (CdS) layer. Transmission electron microscopy, resistivity experiments, and first-principles calculations show that the hole carriers induced by CdS photovoltaic effect are driving the MIT in rutile VO 2 . The insulating-rutile VO 2 phase has been proved and can remain stable for hours. Our finding provides a new approach to produce purely electronically driven MIT in VO 2 , and widens its applications in fast-response, low-energy neuromorphic devices. Previous work has shown that electronic and structural transitions in VO 2 can be decoupled by realizing an electronic transition within a monoclinic phase. Here, the authors extend this to the rutile phase by demonstrating a photodoping-driven transition from an insulating to a metallic rutile phase.

• Publisher: Nature Publishing Group UK,Nature Publishing Group,Nature Portfolio
• Subject: 147/143 / 639/301/119/544 / 639/301/119/995 / 639/766/119/2795 / Cadmium / Cadmium sulfide / CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY / critical phenomena / Electric fields / electronic properties and materials / Electrons / Energy consumption / Experiments / External stimuli / First principles / Humanities and Social Sciences / Insulation / Insulators / Interfaces / Ion beams / Light / Metal-insulator transition / multidisciplinary / Neuromorphic computing / Phase transitions / Photovoltaic effect / Photovoltaics / Physics / Room temperature / Rutile / Science / Science (multidisciplinary) / Spectrum analysis / surfaces / thin films / Transmission electron microscopy / Vanadium / Vanadium dioxide / Vanadium oxides