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Electronic structure of the muonium center as a shallow donor in ZnO

K. Shimomura·K. Nishiyama·R. Kadono
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Abstract

The electronic structure and the location of muonium centers (Mu) in single-crystalline ZnO were determined for the first time. Two species of Mu centers with extremely small hyperfine parameters have been observed below 40 K. Both Mu centers have an axial-symmetric hyperfine structure along with a [0001] axis, indicating that they are located at the AB_{O,//} and BC_{//} sites. It is inferred from their small ionization energy (~6 meV and 50 meV) and hyperfine parameters (~10^{-4} times the vacuum value) that these centers behave as shallow donors, strongly suggesting that hydrogen is one of the primary origins of n type conductivity in as-grown ZnO.

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K. Shimomura, K. Nishiyama, R. Kadono. 2001-12-25. Electronic structure of the muonium center as a shallow donor in ZnO. https://doi.org/10.1103/physrevlett.89.255505

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