@article{oai:repo.qst.go.jp:00084605,
 author = {Atsuo, Kawasuso and Masaki, Maekawa and Atsumi, Miyashita and Ken, Wada and 長嶋, 泰之 and 石田, 明 and Atsuo, Kawasuso and Masaki, Maekawa and Atsumi, Miyashita and Ken, Wada},
 issue = {20},
 journal = {Journal of Physics B: Atomic, Molecular and Optical Physics},
 month = {Nov},
 note = {Positronium emission from wurtzite GaN(0001) and AlN(0001) surfaces was observed by positronium time-of-flight spectroscopy. The positronium energy spectra contained two positronium components distinguished by their energies. Through detailed analyses based on Monte Carlo simulations, these two components were attributed to positronium formed from valence and conduction electrons. The obtained results augment the previous arguments regarding the contribution of conduction electrons to positronium emission from 4H SiC(0001) and Si(111) surfaces.},
 title = {Positronium emission from GaN(0001) and AlN(0001) surfaces},
 volume = {54},
 year = {2021}
}