See also: M.V. Koval’chuk, T.S. Argunova
PACS: 42.25.Fx, 42.25.Kb, 61.72.-y, 61.72.Ff, 61.72.Lk, 61.50.Ah, 68.49.Uv, 79.60.Bm, 78.70.En