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not sufficient conditions for LEEs

Two-level systems in evaporated amorphous silicon

D.R. Queena, X. Liu, J. Karel, H.C. Jacks, T.H. Metcalf, F. Hellman

glass theories - Local excitations in amorphous solids Ji, Wencheng

dangling bonds

https://core.ac.uk/download/pdf/50519584.pdf