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arXiv · 2206.11478

Negatively Charged Muonium and Related Centers in Solids

Takashi U. Ito·Wataru Higemoto·Koichiro Shimomura
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Abstract

Muonium (Mu) centers formed upon implantation of $\mu^+$ in a solid have long been investigated as an experimentally accessible model of isolated hydrogen impurities. Recent discoveries of hydridic centers formed at oxygen vacancies have stimulated a renewed interest in H$^-$ and corresponding Mu$^-$ centers in oxides. However, the two diamagnetic centers, Mu$^+$ and Mu$^-$, are difficult to separate spectroscopically. In this review article, we summarize established and developing methodologies for identifying Mu$^-$ centers in solids, and review recent Mu studies on said centers supposedly formed in mayenite, oxygen-deficient SrTiO$_{3-x}$, and BaTiO$_{3-x}$H$_x$ oxyhydride.

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Takashi U. Ito, Wataru Higemoto, Koichiro Shimomura. 2022-06-23. Negatively Charged Muonium and Related Centers in Solids. https://doi.org/10.7566/jpsj.89.051007

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