Tunable resistivity of correlated VO2(A) and VO2(B) via tungsten doping
Songhee Choi, Gihyeon Ahn, S. J. Moon, Shinbuhm Lee
Abstract
Abstract Applications of correlated vanadium dioxides VO 2 (A) and VO 2 (B) in electrical devices are limited due to the lack of effective methods for tuning their fundamental properties. We find that the resistivity of VO 2 (A) and VO 2 (B) is widely tunable by doping them with tungsten ions. When x < 0.1 in V 1 −x W x O 2 (A), the resistivity decreases drastically by four orders of magnitude with increasing x , while that of V 1 −x W x O 2 (B) shows the opposite behaviour. Using spectroscopic ellipsometry and X-ray photoemission spectroscopy, we propose that correlation effects are modulated by either chemical-strain-induced redistribution of V−V distances or electron-doping-induced band filling in V 1 −x W x O 2 (A), while electron scattering induced by disorder plays a more dominant role in V 1 −x W x O 2 (B). The tunable resistivity makes correlated VO 2 (A) and VO 2 (B) appealing for next-generation electronic devices.