ScholarWorks@성균관대학교

초록

The metal-insulator transition (MIT) in VO2 nanowire devices, driven by electric field-induced nonequilibrium effects, is observed at liquid helium temperature. This unusually low transition temperature is achieved by surface doping VO2 nanowires with gold nanoparticles (NPs). The presence of gold NPs may promote percolative conduction pathways, enhance electronic inhomogeneity, or alter lattice–electron coupling. These effects collectively enable a smoother MIT at a lower electric field compared to pristine VO2 nanowires. An empirical model is used to distinguish Joule heating from electric field contributions, confirming the dominance of nonequilibrium electric field effects. Repeated voltage sweeps further reveal hysteresis and current variations, providing insights into carrier dynamics and correlated electron behavior introduced by NP decoration. These findings advance understanding of the MIT mechanism in VO2 and emphasize the role of surface modifications in tailoring phase transitions at cryogenic temperatures.

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