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Near-Field Nanoimaging of Phases and Carrier Dynamics in Vanadium Dioxide Nanobeams.

ABSTRACT: The stable coexistence of insulating and metallic phases in strained vanadium dioxide (VO₂) has garnered significant research interest due to the intriguing phase transition phenomena. However, the temporal behavior of charge carriers in different phases of VO₂ remains elusive. Herein, we employ near-field optical nanoscopy to capture nanoscale alternating phase domains in bent VO₂ nanobeams. By conducting transient measurements across the different phases, we observed a prolonged carrier recombination lifetime in the metallic phase of VO₂, accompanied by an accelerated diffusion process. Our findings reveal nanoscale carrier dynamics in VO₂ nanobeams, offering insights that can facilitate further investigations into phase-change materials and their potential applications in sensing and microelectromechanical devices.

SUBMITTER: Yang R

PROVIDER: S-EPMC11342413 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature

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Near-Field Nanoimaging of Phases and Carrier Dynamics in Vanadium Dioxide Nanobeams.

Yang Rundi R Li Jingang J Cai Yuhang Y Blankenship Brian W BW Wu Junqiao J Grigoropoulos Costas P CP

ACS photonics 20240717 8

The stable coexistence of insulating and metallic phases in strained vanadium dioxide (VO2) has garnered significant research interest due to the intriguing phase transition phenomena. However, the temporal behavior of charge carriers in different phases of VO2 remains elusive. Herein, we employ near-field optical nanoscopy to capture nanoscale alternating phase domains in bent VO2 nanobeams. By conducting transient measurements across the different phases, we ob ...[more]

PMID: 39184182

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