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DOE OSTI · 1979045

Oxygen vacancy dynamics in monoclinic metallic VO 2 domain structures

Schrecongost, Dustin·Zhang, Hai-Tian·Engel-Herbert, Roman·Cen, Cheng
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Abstract

It was demonstrated recently that the nano-optical and nanoelectronic properties of VO 2 can be spatially programmed through the local injection of oxygen vacancies by atomic force microscope writing. In this work, we study the dynamic evolution of the patterned domain structures as a function of the oxygen vacancy concentration and the time. A threshold doping level is identified that is critical for both the metal–insulator transition and the defect stabilization. The diffusion of oxygen vacancies in the monoclinic phase is also characterized, which is directly responsible for the short lifetimes of sub-100 nm domain structures. This information is imperative for the development of oxide nanoelectronics through defect manipulations.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSFermi-Dirac distributionatomic force microscopycrystallographic defectselectronic band structuremass diffusivitynanoelectronicsnanowiresphase transitionsthin films

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Schrecongost, Dustin, Zhang, Hai-Tian, Engel-Herbert, Roman, Cen, Cheng. 2022-02-24. Oxygen vacancy dynamics in monoclinic metallic VO 2 domain structures. https://doi.org/10.1063/5.0083771

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