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Tunable resistivity of correlated VO₂(A) and VO₂(B) via tungsten doping.

ABSTRACT: Applications of correlated vanadium dioxides VO₂(A) and VO₂(B) in electrical devices are limited due to the lack of effective methods for tuning their fundamental properties. We find that the resistivity of VO₂(A) and VO₂(B) is widely tunable by doping them with tungsten ions. When x < 0.1 in V_1-xW_xO₂(A), the resistivity decreases drastically by four orders of magnitude with increasing x, while that of V_1-xW_xO₂(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-xW_xO₂(A), while electron scattering induced by disorder plays a more dominant role in V_1-xW_xO₂(B). The tunable resistivity makes correlated VO₂(A) and VO₂(B) appealing for next-generation electronic devices.

SUBMITTER: Choi S

PROVIDER: S-EPMC7297976 | biostudies-literature |

REPOSITORIES: biostudies-literature

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