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arXiv · 2402.08894

Nano-scale dynamics of hydrogen in VO$_{2}$ studied by $\mu $SR

H. Okabe·M. Hiraishi·A. Koda·Y. Matsushita·T. Ohsawa·N. Ohashi·R. Kadono
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Abstract

Hydrogen dynamics in the nanoscale region of VO$_{2}$ was investigated by muon spin rotation/relaxation ($\mu $SR) technique. Positively charged muon acts as a light radioisotope of proton and can be used as a probe to explore the inside of materials from an atomic perspective. By analyzing the muon hopping rate and the spatial distribution of the $^{51}$V nuclear magnetic moments, we have identified two types of diffusion paths in VO$_{2}$ (via oxygen-muon bonds or defects) and the potential of a high diffusion coefficient in the 10$^{-10}$ cm$^{2}$/s range at ambient temperature. Our results provide valuable information for developing hydrogen-driven VO$_{2}$--related electronic devices.

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H. Okabe, M. Hiraishi, A. Koda, Y. Matsushita, T. Ohsawa, N. Ohashi, R. Kadono. 2024-02-14. Nano-scale dynamics of hydrogen in VO$_{2}$ studied by $\mu $SR. https://doi.org/10.1103/physrevmaterials.8.024602

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