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

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